Cita APA

Library Association, Walford, A. J., Mullay, M., & Schlicke, P. (1999). Walford's guide to reference materials. Library Association Pub.

Citación estilo Chicago

Library Association, A. J. Walford, Marilyn Mullay, and Priscilla Schlicke. Walford's Guide to Reference Materials. London: Library Association Pub, 1999.

Cita MLA

Library Association, et al. Walford's Guide to Reference Materials. Library Association Pub, 1999.