@incollection {jaehne1999q,
	title = {Neighborhood operators},
	year = {1999},
	pages = {93--124},
	publisher = {Academic Press},
	chapter = {5},
	author = {Bernd J{\"a}hne and Bernd J{\"a}hne and Horst Hau{\ss}ecker},
	editor = {Peter Gei{\ss}ler}
}
