@book{15876,
	author = {Collatz, L. and Wetterling, W. and Wetterling, W. ; jt. auth.},
	title = {Optimization problems},
	publisher = {Springer-Verlag},
	year = {1975},
	series = {Applied Mathematical Sciences },
	address = {New York},
	note = {"Tr. from the German by P. Wadsack".}
}