توثيق جمعية علم النفس الأمريكية APA (الطبعة السابعة)

Merrill, W. S. (1939). Code for classifiers: Principles governing the consistent placing o books in a system of classification (2nd ed.). American Library Association.

توثيق أسلوب شيكاغو (الطبعة السابعة عشر)

Merrill, William S. Code for Classifiers: Principles Governing the Consistent Placing O Books in a System of Classification. 2nd ed. Chicago: American Library Association, 1939.

توثيق جمعية اللغة المعاصرة MLA (الإصدار التاسع)

Merrill, William S. Code for Classifiers: Principles Governing the Consistent Placing O Books in a System of Classification. 2nd ed. American Library Association, 1939.