@incollection {spies1999,
	title = {Analyzing particle movements at soil interfaces},
	volume = {3: Systems and Applications},
	year = {1999},
	pages = {699-718},
	publisher = {Academic Press},
	chapter = {32},
	author = {Hagen Spies and Oliver Beringer and Hermann Gr{\"o}ning and Horst Hau{\ss}ecker and Bernd J{\"a}hne and Horst Hau{\ss}ecker and Peter Gei{\ss}ler}
}
