APA (7th ed.) Citation

Gilbert Mudge, I. (1936). Guide to Reference Books (6a ed.). American Library Association.

Chicago Style (17th ed.) Citation

Gilbert Mudge, Isadore. Guide to Reference Books. 6a ed. Chicago: American Library Association, 1936.

MLA (9th ed.) Citation

Gilbert Mudge, Isadore. Guide to Reference Books. 6a ed. American Library Association, 1936.