@incollection {barron2001,
	title = {The fusion of image and range flow},
	year = {2001},
	pages = {174--192},
	publisher = {Springer},
	doi = {10.1007/3-540-45134-X_13},
	author = {John L. Barron and Hagen Spies},
	editor = {R. Klette and Huang, T. and Gimel{\textquoteright}farb, G.}
}
@conference {koehler1999,
	title = {Fluidisation and deformation of submerged soil due to fluctuating water level},
	booktitle = {XII Europ. Conference on Soil Mechanics and Geotechnical Engineering},
	year = {1999},
	pages = {1109--1115},
	author = {H.-J. K{\"o}hler and Hagen Spies and Oliver Beringer and Horst Hau{\ss}ecker}
}
