Cita APA (7th ed.)

Philippines. Bureau of Posts. Planning Division. (1977). Post office classification study. The Bureau.

Cita Chicago (17th ed.)

Philippines. Bureau of Posts. Planning Division. Post Office Classification Study. [Manila]: The Bureau, 1977.

Cita MLA (9th ed.)

Philippines. Bureau of Posts. Planning Division. Post Office Classification Study. The Bureau, 1977.