Cita APA (7th ed.)

Romulo, C. P. (1980). The challenges of the 80's. Ministry of Foreign Affairs.

Cita Chicago (17th ed.)

Romulo, Carlos Pena. The Challenges of the 80's. Manila: Ministry of Foreign Affairs, 1980.

Cita MLA (9th ed.)

Romulo, Carlos Pena. The Challenges of the 80's. Ministry of Foreign Affairs, 1980.