@book{50091,
	author = {Penna, Carlos Victor and Sewell, Philip Hooper.},
	title = {The planning of library and documentation services},
	publisher = {Unesco},
	year = {1970, 1972 printing.},
	series = {Unesco manuals for libraries ; 17},
	address = {Paris},
	edition = {2d ed. rev. and enl.},
	note = {First ed. published in 1967 under title: Planning library services.}
}