Παραπομπή APA

Krishan Kumar. (1988). Theory of classification. Rev ed (4th ed.). N Delhi.

Παραπομπή Chicago Style

Krishan Kumar. Theory of Classification. Rev Ed. 4th ed. Vikas pub house: N Delhi, 1988.

Παραπομπή MLA

Krishan Kumar. Theory of Classification. Rev Ed. 4th ed. N Delhi, 1988.