@book{8668,
	author = {Tietze, Heinrich and Hofstadter, Beatrice Kevitt ; ed.},
	title = {Famous problems of mathematics; solved and unsolved problems from antiquity to modern times},
	publisher = {Graylock Press},
	year = {1965},
	address = {Baltimore},
	note = {"Tr. from the 2nd. (1959) rev. German ed.".}
}