Cita APA (7th ed.)

Dittmann, H., & Hardy, J. (2007). Learn Library of Congress classification (2nd North American ed.). TotalRecall Publications, Inc..

Cita Chicago (17th ed.)

Dittmann, Helena, i Jane Hardy. Learn Library of Congress Classification. 2nd North American ed. Friendswood, Tex: TotalRecall Publications, Inc., 2007.

Cita MLA (9th ed.)

Dittmann, Helena, i Jane Hardy. Learn Library of Congress Classification. 2nd North American ed. TotalRecall Publications, Inc., 2007.