@book{50,
	author = {Prager, B. and Jacobson, P.},
	title = {Beilsteins Handbuch der Organischen chemie Supplementary Band (vol-03 to 04)},
	publisher = {Berlin Verlag Von Julius Springer},
	year = {1929},
	series = {3 to 4},
	address = {Berlin}
}