Philippines. National Science Development Board. (1976). National Science Development Board. National Media Production Center.
Cita Chicago (17th ed.)Philippines. National Science Development Board. National Science Development Board. Manila: National Media Production Center, 1976.
Cita MLA (9th ed.)Philippines. National Science Development Board. National Science Development Board. National Media Production Center, 1976.
Atenció: Aquestes cites poden no estar 100% correctes.