Tom Rune Lauknes
@norceresearch.no
NORCE
RESEARCH, TEACHING, or OTHER INTERESTS
Engineering, Multidisciplinary
Scopus Publications
Scholar Citations
Scholar h-index
Scholar i10-index
Scopus Publications
Johnson Bailey, Vahid Akbari, Tao Liu, Tom Rune Lauknes, and Armando Marino
Institute of Electrical and Electronics Engineers (IEEE)
Satellite monitoring of icebergs in the Arctic region is paramount for the safety of shipping and maritime activities. The potential of polarimetric synthetic aperture radar data in enhancing detection capabilities of icebergs under interchangeable and challenging conditions is explored in this work. We introduce RADARSAT-2 quad-pol C-band data to detect icebergs in Kongsfjorden, Svalbard. The location contains two tidewater glaciers and is chosen because multiple processes are present in this region, such as ice formation and its relationship with the glaciers, freshwater discharge. Six state-of-the-art detectors are tested for detection performance. These are the dual-intensity polarization ratio anomaly detector, polarimetric notch filter, polarimetric match filter, symmetry, polarimetric whitening filter (PWF), and optimal polarimetric detector (OPD). In addition, we also tested the parameters of the Cloude–Pottier decomposition. In this study, we make use of a ground-based radar for validation and comparison with satellite images. We show that in calm sea-state conditions, the OPD and PWF detectors give high probability of detection (PD) values of 0.7–0.8 when the probability of false alarm (PF) value is 0.01–0.05, compared with choppy sea conditions where the same detectors have degraded performance (PD = 0.5–0.7). Target-to-clutter ratio (TCR) values for each polarization channel is also extracted and compared to the icebergs’ dimensions. The ground-based radar shows higher values in TCR, compared with satellite images. These findings corroborate previous work and show that sea-ice activity, surface roughness, incidence angle, weather, and sea-state conditions all affect the sensitivity of the detectors for this task.
Małgorzata Błaszczyk, Mateusz Moskalik, Mariusz Grabiec, Jacek Jania, Waldemar Walczowski, Tomasz Wawrzyniak, Agnieszka Strzelewicz, Eirik Malnes, Tom Rune Lauknes, and W. Tad Pfeffer
American Geophysical Union (AGU)
AbstractMany Arctic marine‐terminating glaciers have undergone rapid retreats in recent decades. Seasonal and year‐to‐year variations in terminus position act on all tidewater glaciers, but the key controls on those changes vary from region to region. Here, we examined seasonal and decadal changes in termini positions of seven tidewater glaciers in the inner part of Hornsund, the southernmost fjord of Spitsbergen (Svalbard Archipelago), based on a variety of data from 1992 to 2020. Combining satellite imagery, basic meteorological data (air temperature, positive degree day index (PDD), liquid precipitation), sea surface temperature (SST), mean temperature in the glacier forefield bays, fast sea ice cover, and bathymetry near the glacier front, we examined the influence of potential controlling parameters on interannual and seasonal variability of the glacier termini. We found regional synchrony between terminus advance/retreat and climate variables. At a regional scale, annual fluctuation changes are related to PDD and SST, while summer fluctuations are linked to PDD, although individual glaciers are shown to have differing sensitivities to potential climate drivers. We also found that the retreat period in Hornsund generally lasts from June to October‐December. Onset of the retreat is related to sea and air temperature, and in some cases follows the disappearance of the ice cover. These results indicate that the expected increase in meltwater runoff in Svalbard, the input of relatively warm Atlantic water to the fjord, and the increasing trend of longer summer and warmer winter periods will have implications for glacier velocity and frontal ablation.
Bernd Etzelmüller, Justyna Czekirda, Florence Magnin, Pierre-Allain Duvillard, Ludovic Ravanel, Emanuelle Malet, Andreas Aspaas, Lene Kristensen, Ingrid Skrede, Gudrun D. Majala,et al.
Copernicus GmbH
Abstract. The warming and subsequent degradation of mountain permafrost within alpine areas represent an important process influencing the stability of steep slopes and rock faces. The unstable and monitored slopes of Mannen (Møre and Romsdal county, southern Norway) and Gámanjunni-3 (Troms and Finnmark county, northern Norway) were classified as high-risk sites by the Norwegian Geological Survey (NGU). Failure initiation has been suggested to be linked to permafrost degradation, but the detailed permafrost distribution at the sites is unknown. Rock wall (RW) temperature loggers at both sites have measured the thermal regime since 2015, showing mean rock surface temperatures between 2.5 and −1.6 ∘C depending on site and topographic aspect. Between 2016 and 2019 we conducted 2D and 3D electrical resistivity tomography (ERT) surveys on the plateau and directly within the rock wall back scarp of the unstable slopes at both sites. In combination with geophysical laboratory analysis of rock wall samples from both sites, the ERT soundings indicate widespread permafrost areas, especially at Gámanjunni-3. Finally, we conducted 2D thermal modelling to evaluate the potential thermal regime, along with an analysis of available displacement rate measurements based on Global Navigation Satellite System (GNSS) and ground- and satellite-based interferometric synthetic aperture radar (InSAR) methods. Surface air and ground temperatures have increased significantly since ca. 1900 by 1 and 1.5 ∘C, and the highest temperatures have been measured and modelled since 2000 at both study sites. We observed a seasonality of displacement, with increasing velocities during late winter and early spring and the highest velocities in June, probably related to water pressure variations during snowmelt. The displacement rates of Gámanjunni-3 rockslide co-vary with subsurface resistivity and modelled ground temperature. Increased displacement rates seem to be associated with sub-zero ground temperatures and higher ground resistivity. This might be related to the presence of ground ice in fractures and pores close to the melting point, facilitating increased deformation. The study demonstrates and discusses the possible influence of permafrost, at least locally, on the dynamics of large rock slope instabilities.
Line Rouyet, Karianne Staalesen Lilleøren, Martina Böhme, Louise Mary Vick, Reynald Delaloye, Bernd Etzelmüller, Tom Rune Lauknes, Yngvar Larsen, and Lars Harald Blikra
Frontiers Media SA
Mountain slopes in periglacial environments are affected by frost- and gravity-driven processes that shape the landscape. Both rock glaciers and rockslides have been intensively inventoried worldwide. Although most inventories are traditionally based on morphologic criteria, kinematic approaches based on satellite remote sensing have more recently been used to identify moving landforms at the regional scale. In this study, we developed simplified Interferometric Synthetic Aperture Radar (InSAR) products to inventory ground velocity in a region in Northern Norway covering approximately 7,500 km2. We used a multiple temporal baseline InSAR stacking procedure based on 2015–2019 ascending and descending Sentinel-1 images to take advantage of a large set of interferograms and exploit different detection capabilities. First, moving areas are classified according to six velocity brackets, and morphologically associated to six landform types (rock glaciers, rockslides, glaciers/moraines, talus/scree deposits, solifluction/cryoturbation and composite landforms). The kinematic inventory shows that the velocity ranges and spatial distribution of the different types of slope processes vary greatly within the study area. Second, we exploit InSAR to update pre-existing inventories of rock glaciers and rockslides in the region. Landform delineations and divisions are refined, and newly detected landforms (54 rock glaciers and 20 rockslides) are incorporated into the databases. The updated inventories consist of 414 rock glacier units within 340 single- or multi-unit(s) systems and 117 rockslides. A kinematic attribute assigned to each inventoried landform documents the order of magnitude of the creep rate. Finally, we show that topo-climatic variables influence the spatial distribution of the rock glaciers. Their mean elevation increases toward the continental interior with a dominance of relict landforms close to the land-sea margin and an increased occurrence of active landforms further inland. Both rock glaciers and rockslides are mostly located on west-facing slopes and in areas characterised by strongly foliated rocks, which suggests the influence of geological preconditioning factors. The study demonstrates the value of semi-quantitative InSAR products to characterise kinematic information at large scale and exploit the results for periglacial research. It highlights the complementarity of both kinematic and morphologic approaches for inventorying slope processes.
Guodong Zhang, Zhichao Xu, Feng Wang, Dongkai Yang, and Jin Xing
MDPI AG
The elevation angle influence on coastal GNSS-R ocean code-based altimetry for GPS signals (L1 C/A and L5) and BDS B1 signals is investigated, and the corresponding correction method is presented. The study first focuses on the coastal ocean altimetry method, including the general experiment geometry and the code delay estimation using the single-point tracking algorithm. The peak power and the maximum first derivative are used as the location of the specular point. Then, the sensitivity of the height retrieved using the above coastal ocean altimetry method to elevation angle is analyzed based on the Z-V model. It can be seen that the elevation angle has a significant influence on the height retrieval, which will affect the precision of the coastal GNSS-R ocean altimetry. Finally, two correction methods, the model-driven method and the data-driven method, are proposed. The coastal altimetry experiments demonstrate that the correction methods can correct the elevation angle influence, and the data-driven method is more effective. The experimental results show that, after correcting the elevation angle influence, the code-based altimetry precision of the GPS L1 C/A signal, L5 signal, and BDS B1 signal can be up to the meter level, decimeter level (less than 4 decimeters), and meter level with respect to a reference tide gauge (TG) data set, respectively, without smoothing over time. These results provide information to guide the sea surface height retrieval using coastal GNSS-R, especially multi-satellite observation and GNSS signal with a higher chipping rate.
L. Rouyet, O. Karjalainen, P. Niittynen, J. Aalto, M. Luoto, T. R. Lauknes, Y. Larsen, and J. Hjort
American Geophysical Union (AGU)
AbstractPeriglacial environments are characterized by highly dynamic landscapes. Freezing and thawing lead to ground movement, associated with cryoturbation and solifluction. These processes are sensitive to climate change and variably distributed depending on multiple environmental factors. In this study, we used multi‐geometry Sentinel‐1 Synthetic Aperture Radar Interferometry (InSAR) to investigate the spatial distribution of the mean annual ground velocity in a mountainous landscape in Northern Norway. Statistical modeling was employed to examine how periglacial ground velocity is related to environmental variables characterizing the diverse climatic, geomorphic, hydrological and biological conditions within a 148 km2 study area. Two‐dimensional (2D) InSAR results document mean annual ground velocity up to 15 mm/yr. Vertical and horizontal velocity components in the East–West plane show variable spatial distribution, which can be explained by the characteristics of cryoturbation and solifluction operating differently over flat and sloping terrain. Statistical modeling shows that slope angle and mean annual air temperature variables are the most important environmental factors explaining the distribution of the horizontal and vertical components, respectively. Vegetation and snow cover also have a local influence, interpreted as indicators of the ground material and moisture conditions. The results show contrasted model performance depending on the velocity component used as a response variable. In general, our study highlights the potential of integrating radar remote sensing and statistical modeling to investigate mountainous regions and better understand the relations between environmental factors, periglacial processes and ground dynamics.
Shridhar D. Jawak, Bo N. Andersen, Veijo A. Pohjola, Øystein Godøy, Christiane Hübner, Inger Jennings, Dariusz Ignatiuk, Kim Holmén, Agnar Sivertsen, Richard Hann,et al.
MDPI AG
Svalbard Integrated Arctic Earth Observing System (SIOS) is an international partnership of research institutions studying the environment and climate in and around Svalbard. SIOS is developing an efficient observing system, where researchers share technology, experience, and data, work together to close knowledge gaps, and decrease the environmental footprint of science. SIOS maintains and facilitates various scientific activities such as the State of the Environmental Science in Svalbard (SESS) report, international access to research infrastructure in Svalbard, Earth observation and remote sensing services, training courses for the Arctic science community, and open access to data. This perspective paper highlights the activities of SIOS Knowledge Centre, the central hub of SIOS, and the SIOS Remote Sensing Working Group (RSWG) in response to the unprecedented situation imposed by the global pandemic coronavirus (SARS-CoV-2) disease 2019 (COVID-19). The pandemic has affected Svalbard research in several ways. When Norway declared a nationwide lockdown to decrease the rate of spread of the COVID-19 in the community, even more strict measures were taken to protect the Svalbard community from the potential spread of the disease. Due to the lockdown, travel restrictions, and quarantine regulations declared by many nations, most physical meetings, training courses, conferences, and workshops worldwide were cancelled by the first week of March 2020. The resumption of physical scientific meetings is still uncertain in the foreseeable future. Additionally, field campaigns to polar regions, including Svalbard, were and remain severely affected. In response to this changing situation, SIOS initiated several operational activities suitable to mitigate the new challenges resulting from the pandemic. This article provides an extensive overview of SIOS’s Earth observation (EO), remote sensing (RS) and other operational activities strengthened and developed in response to COVID-19 to support the Svalbard scientific community in times of cancelled/postponed field campaigns in Svalbard. These include (1) an initiative to patch up field data (in situ) with RS observations, (2) a logistics sharing notice board for effective coordinating field activities in the pandemic times, (3) a monthly webinar series and panel discussion on EO talks, (4) an online conference on EO and RS, (5) the SIOS’s special issue in the Remote Sensing (MDPI) journal, (6) the conversion of a terrestrial remote sensing training course into an online edition, and (7) the announcement of opportunity (AO) in airborne remote sensing for filling the data gaps using aerial imagery and hyperspectral data. As SIOS is a consortium of 24 research institutions from 9 nations, this paper also presents an extensive overview of the activities from a few research institutes in pandemic times and highlights our upcoming activities for the next year 2021. Finally, we provide a critical perspective on our overall response, possible broader impacts, relevance to other observing systems, and future directions. We hope that our practical services, experiences, and activities implemented in these difficult times will motivate other similar monitoring programs and observing systems when responding to future challenging situations. With a broad scientific audience in mind, we present our perspective paper on activities in Svalbard as a case study.
A. Malin Johansson, Eirik Malnes, Sebastian Gerland, Anca Cristea, Anthony P. Doulgeris, Dmitry V. Divine, Olga Pavlova, and Tom Rune Lauknes
Cambridge University Press (CUP)
AbstractSynthetic Aperture Radar (SAR) satellite images are used to monitor Arctic sea ice, with systematic data records dating back to 1991. We propose a semi-supervised classification method that separates open water from sea ice and can utilise ERS-1/2, Envisat ASAR, RADARSAT-2 and Sentinel-1 SAR images. The classification combines automatic segmentation with a manual segment selection stage. The segmentation algorithm requires only the backscatter intensities and incidence angle values as input, therefore can be used to establish a consistent decadal sea ice record. In this study we investigate the sea ice conditions in two Svalbard fjords, Kongsfjorden and Rijpfjorden. Both fjords have a seasonal ice cover, though Rijpfjorden has a longer sea ice season. The satellite image dataset has weekly to daily records from 2002 until now, and less frequent records between 1991 and 2002. Time overlap between different sensors is investigated to ensure consistency in the reported sea ice cover. The classification results have been compared to high-resolution SAR data as well as in-situ measurements and sea ice maps from Ny-Ålesund. For both fjords the length of the sea ice season has shortened since 2002 and for Kongsfjorden the maximum sea ice coverage is significantly lower after 2006.
Clas Veiback, Jonatan Olofsson, Tom Rune Lauknes, and Gustaf Hendeby
Institute of Electrical and Electronics Engineers (IEEE)
Tracked targets often exhibit common behaviors due to influences from the surrounding environment, such as wind or obstacles, which are usually modeled as noise. Here, these influences are modeled using sparse Gaussian processes that are learned online together with the state inference using an extended Kalman filter. The method can also be applied to time-varying influences and identify simple dynamic systems. The method is evaluated with promising results in a simulation and a real-world application.
Louise M. Vick, Martina Böhme, Line Rouyet, Steffen G. Bergh, Geoffrey D. Corner, and Tom Rune Lauknes
Springer Science and Business Media LLC
AbstractGravitational forcing of oversteepened rock mass leads to progressive failure, including rupture, creeping, sliding and eventual avalanching of the unstable mass. As the point of rupture initiation typically follows pre-existing structural discontinuities within the rock mass, understanding the structural setting of slopes is necessary for an accurate characterisation of the hazards and estimation of the risk to life and infrastructure. Northern Norway is an alpine region with a high frequency of large rock slope deformations. Inherited structures in the metamorphic bedrock create a recurring pattern of anisotropy, that, given certain valley orientations, causes mass instability. We review the geomorphology, structural mechanics and kinematics of nine deforming rock slopes in Troms County, with the aim of linking styles of deformation. The limits of the unstable rock mass follow either foliation planes, joint planes or inherited faults, depending on the valley aspect, slope angle, foliation dip and proximity to fault structures. We present an updated geotechnical model of the different failure mechanisms, based on the interpretations at each site of the review.
Jonatan Olofsson, Gustaf Hendeby, Tom Rune Lauknes, and Tor Arne Johansen
Springer Science and Business Media LLC
Line Rouyet, Tom Rune Lauknes, Hanne H. Christiansen, Sarah M. Strand, and Yngvar Larsen
Elsevier BV
John F Dehls, Yngvar Larsen, Petar Marinkovic, Tom Rune Lauknes, Daniel Stodle, and Dag Anders Moldestad
IEEE
InSAR Norway, a public national ground motion service, based on Copernicus Sentinel-1 data, was launched in November 2018. The service provides regularly updated ground motion time series on over two billion locations in Norway. The service provides this data freely and openly to all interested users, through a web browser interface. Within the government, this data in instrumental for landslide hazard and risk assessment as well as monitoring. Other applications include evaluation of urban subsidence and infrastructure monitoring. Many scientific applications also benefit, such as in the fields of geomorphology and geodesy.InSAR Norway is operated by the Geological Survey of Norway, with cofunding from the Norwegian Space Centre and the Norwegian Water and Energy Directorate. Processing is done on a high-performance computing cluster (HPCC) using software developed by the KSAT-GMS partnership (NORCE – formerly NORUT, PPO.labs and Kongsberg Satellite Services).
M. Böhme, R.L. Hermanns, J. Gosse, P. Hilger, T. Eiken, T.R. Lauknes, and J.F. Dehls
Geological Society of America
Vahid Akbari, Tom Rune Lauknes, Line Rouyet, Jean Negrel, and Torbjorn Eltoft
IEEE
Calving of icebergs at the tidewater glacier fronts is a component of the mass loss in Polar regions. Studying the regional distribution of icebergs, their volume, motion, and interaction with the environment is of interest. Here, we present the results from a fieldwork campaign conducted in Kongsfjorden, Svalbard in April 2016, where both satellite and ground-based remote sensing instruments were used to observe dynamics of sea ice, icebergs, and growlers. We used a ground-based radar system, imaging the study area every second minute during five days. During the same observation period, we collected four RADARSAT-2 (RS-2) quad-pol images, that are used for automatic detection of icebergs. In addition, the fieldwork team collected GPS positions of some drifting and grounded icebergs in the fjord to be used as ground-truth data. The comparison and combination of satellite, ground-based radar, and in-situ data contribute to cross-validate the results.
H. Ø. Eriksen, L. Rouyet, T. R. Lauknes, I. Berthling, K. Isaksen, H. Hindberg, Y. Larsen, and G. D. Corner
American Geophysical Union (AGU)
AbstractRecent acceleration of rock glaciers is well recognized in the European Alps, but similar behavior is hardly documented elsewhere. Also, the controlling factors are not fully understood. Here we provide evidence for acceleration of a rock glacier complex in northern Norway, from 62 years of remote sensing data. Average annual horizontal velocity measured by aerial feature tracking increased from ~0.5 myr−1 (1954–1977) to ~3.6 myr−1 (2006–2014). Measured by satellite synthetic aperture radar offset‐tracking, averages increased from ~4.9 to ~9.8 myr−1 (2009–2016) and maximum velocities from ~12 to ~69 myr−1. Kinematic analysis reveals different spatial‐temporal trends in the upper and the lower parts of the rock glacier complex, suggesting progressive detachment of the faster front. We suggest that permafrost warming, topographic controls, and increased water access to deeper permafrost layers and internal shear zones can explain the kinematic behavior.
Markus Eckerstorfer, Harald Øverli Eriksen, Line Rouyet, Hanne H. Christiansen, Tom Rune Lauknes, and Lars Harald Blikra
Wiley
AbstractThe ability to continuously monitor the dynamic response of periglacial landforms in a climate change context is of increasing scientific interest. Satellite radar interferometry provides information on surface displacement that can be related to periglacial processes. Here we present a comparison of two‐dimensional (2D) surface displacement rates and geomorphological mapping at periglacial landform and sediment scale from the mountain Nordnesfjellet in northern Norway. Hence, 2D Interferometric Synthetic Aperture Radar (InSAR) results stem from a 2009–2014 TerraSAR‐X dataset from ascending and descending orbits, decomposed into horizontal displacement vectors along an east–west plane, vertical displacement vectors and combined displacement velocity. Geomorphological mapping was carried out on aerial imagery and validated in the field. This detailed landform and sediment type mapping revealed an altitudinal distribution dominated by, weathered bedrock blockfields, surrounded primarily by slightly, to non‐vegetated solifluction landforms at the mountain tops. Below, an active rockslide and associated rockfall deposits are located on the steep east‐facing side of the study area, whereas glacial sediments dominate on the gentler western side. We show that 2D InSAR correctly depicts displacement rates that can be associated with typical deformation patterns for flat‐lying or inclined landforms, within and below the regional permafrost limit, for both wet and dry areas. A net lowering of the entire landscape caused by general denudation of the periglacial landforms and sediments is here quantified for the first time using radar remote sensing. Copyright © 2018 John Wiley & Sons, Ltd.
Jean Negrel, Sebastian Gerland, Anthony P. Doulgeris, Tom Rune Lauknes, and Line Rouyet
Cambridge University Press (CUP)
ABSTRACTResearch on young thin sea ice is essential to understand the changes in the Arctic. But it is also the most challenging to investigate, both in situ and from satellites. If satellite remote-sensing techniques are developing rapidly, fieldwork remains crucial for the mandatory validation of such data. In April 2016, an Arctic fieldwork campaign was conducted at Kongsfjorden, Svalbard. This campaign provided an opportunity to combine various techniques to record the fjord ice properties ranging from local field sampling to broader ground-based and satellite radar remote sensing of the fjord. Tracking the boat used to access the field sites with hand-held GPS devices offered a good opportunity to map fjord ice and assess the limits of radar identification of small icebergs and thin ice. During 1 week, 17 icebergs and the thin ice edges in two different locations were mapped. The GPS tracks present a good agreement with the Radarsat-2 data analysis for one of the two ice edges. The second ice edge track only partly corresponds to the radar scene. Ice movement, recorded by a ground-based radar, is likely to explain this result. Grounded icebergs could be identified in both Radarsat-2 and ground-based radar.
Line Rouyet, Lene Kristensen, Marc-Henri Derron, Clément Michoud, Lars Harald Blikra, Michel Jaboyedoff, and Tom Rune Lauknes
Elsevier BV
Harald Øverli Eriksen, Tom Rune Lauknes, Yngvar Larsen, Geoffrey D. Corner, Steffen G. Bergh, John Dehls, and Halfdan Pascal Kierulf
Elsevier BV
Harald Øverli Eriksen, Steffen G. Bergh, Yngvar Larsen, Ingrid Skrede, Lene Kristensen, Tom Rune Lauknes, Lars Harald Blikra, and Halfdan Pascal Kierulf
Geological Society of Norway
This study combines remote sensing data from groundand satellite-based radar to calculate 3D displacement vectors for the Jettan rockslide, Troms, northern Norway. Using 3D displacement vectors, aspect data and strain rates in conjunction with structure (foliation, faults, fractures), geomorphological elements (ridges, scarps, terraces, depressions), topography and borehole data, we identify zones undergoing displacement, e.g., extension and compression, displacement intoor out-of-the-slope and/or various degrees of tilting. Our results show variable 3D displacement velocities, from north to south, that segment the rockslide into distinct domains. Displacement patterns are structurally controlled, as spatial variation in azimuth and plunge of 3D displacement vectors can be related to variation in attitudes of the host-rock foliation, faults and fractures. In the north, a complex graben system surrounded by orthogonal NW–SE and NE–SW-trending geomorphological elements, shows a repeated stepping 3D displacement pattern. This may indicate a complex fault geometry at depth, including stepped and discontinuous slide surfaces. We interpret 3D displacement into-the-slope in the upper part, and out-of-the-slope in the lower part, to be back-rotation of antithetic blocks with planar fractures becoming curved/listric gliding surfaces with depth. Downslope reduction in velocity indicates compression and stacking of blocks. In the southern area, N–S-trending geomorphological elements are arranged parallel to the hillslope. 3D displacement vectors show a more homogenous displacement pattern indicating movement along planar, hillslope-parallel, fracture sets at depth. We propose a structuralcontrolled slope displacement model including alternate planarand wedge-failure, in addition to displacement along planar and listric fractures merging into foliation at depth. Using the Jettan rockslide as a case study, we show how remote sensing data may aid examination of structural and topographic controls on rockslide kinematics, thus giving new insights into subsurface geometry
Clément Michoud, Valérie Baumann, Tom Rune Lauknes, Ivanna Penna, Marc-Henri Derron, and Michel Jaboyedoff
Springer Science and Business Media LLC
M Böhme, H Bunkholt, T Oppikofer, J Dehls, R Hermanns, H Eriksen, T Lauknes, and T Eiken
CRC Press