APA (7th ed.) Citation

Merrill, W. S. (1939). Code for classifiers; principles governing the consistent placing of books in a system of classification (2nd ed.). American library association.

Chicago Style (17th ed.) Citation

Merrill, William Stetson. Code for Classifiers; Principles Governing the Consistent Placing of Books in a System of Classification. 2nd ed. Chicago: American library association, 1939.

MLA (9th ed.) Citation

Merrill, William Stetson. Code for Classifiers; Principles Governing the Consistent Placing of Books in a System of Classification. 2nd ed. American library association, 1939.