Cita APA

Penna, C. V., Sewell, P. H., & Liebaers, H. (1970). The planning of library and documentation services (2d ed. rev. and enl.). Unesco.

Citación estilo Chicago

Penna, Carlos Víctor, Philip Hooper Sewell, and Herman Liebaers. The Planning of Library and Documentation Services. 2d ed. rev. and enl. Paris: Unesco, 1970.

Cita MLA

Penna, Carlos Víctor, et al. The Planning of Library and Documentation Services. 2d ed. rev. and enl. Unesco, 1970.