APA (7th ed.) Citation

Spengler, J. J., & Duncan, O. D. (1956). Population theory and policy: Selected readings. Free Press.

Chicago Style (17th ed.) Citation

Spengler, Joseph John, and Otis Dudley Duncan. Population Theory and Policy: Selected Readings. Glencoe: Free Press, 1956.

MLA (9th ed.) Citation

Spengler, Joseph John, and Otis Dudley Duncan. Population Theory and Policy: Selected Readings. Free Press, 1956.