Παραπομπή APA

Penland P R. (1960). Colon classification. Sarada Ranganathan Endowment.

Παραπομπή Chicago Style

Penland P R. Colon Classification. Bangalore: Sarada Ranganathan Endowment, 1960.

Παραπομπή MLA

Penland P R. Colon Classification. Sarada Ranganathan Endowment, 1960.