Philippines (Republic). Office of the President. Presidential Economic Staff. (1969). Provincial profile of Ilocos Sur. The PES.
Chicago Style (17th ed.) CitationPhilippines (Republic). Office of the President. Presidential Economic Staff. Provincial Profile of Ilocos Sur. Manila: The PES, 1969.
MLA (9th ed.) CitationPhilippines (Republic). Office of the President. Presidential Economic Staff. Provincial Profile of Ilocos Sur. The PES, 1969.
Warning: These citations may not always be 100% accurate.