Landis, P. H. (1948). Population problems: A cultural interpretation. American Book Company.
Lua i Stíl Chicago (17ú heag.)Landis, Paul Henry. Population Problems: A Cultural Interpretation. New York: American Book Company, 1948.
Lua MLA (9ú heag.)Landis, Paul Henry. Population Problems: A Cultural Interpretation. American Book Company, 1948.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.