@book{11679,
	author = {Zieschang, Heiner and Vogt, Elmar},
	title = {Surfaces and planar discontinuous groups},
	publisher = {Springer-Verlag,},
	year = {1980},
	series = {Lecture notes in Mathematics},
	address = {Berlin:},
	note = {"Translated from the German by J. Stillwell"}
}