APA (7e ed.) Bronvermelding

Lewis, R. O. (1958). Soil conservation in the Philippines: Terminal report, February 15, 1956-February 1, 1958. United States Operations Mission to the Philippines.

Chicago (17e ed.) Bronvermelding

Lewis, Ralph O. Soil Conservation in the Philippines: Terminal Report, February 15, 1956-February 1, 1958. [Manila]: United States Operations Mission to the Philippines, 1958.

MLA (9e ed.) Bronvermelding

Lewis, Ralph O. Soil Conservation in the Philippines: Terminal Report, February 15, 1956-February 1, 1958. United States Operations Mission to the Philippines, 1958.