APA (7th ed.) Citation

Terry, C. E., & Pellens, M. (1970). The opium problem. Patterson Smith.

Chicago Style (17th ed.) Citation

Terry, Charles Edward, and Mildred Pellens. The Opium Problem. Montclair, NJ: Patterson Smith, 1970.

MLA (9th ed.) Citation

Terry, Charles Edward, and Mildred Pellens. The Opium Problem. Patterson Smith, 1970.