R.R. Bowker Company. (1957). Subject guide to books in print. R.R. Bowker Co..
Cita Chicago (17th ed.)R.R. Bowker Company. Subject Guide to Books in Print. New York: R.R. Bowker Co., 1957.
Cita MLA (8th ed.)R.R. Bowker Company. Subject Guide to Books in Print. R.R. Bowker Co., 1957.
Atenció: Aquestes cites poden no estar 100% correctes.