APA استشهاد

Porterfield, J. D. Community Health in United in the United states. Voice of America.

استشهاد بنمط شيكاغو

Porterfield, John D. Community Health in United in the United States. New York: Voice of America.

MLA استشهاد

Porterfield, John D. Community Health in United in the United States. Voice of America.