Cita APA (7th ed.)

Hughes, F. P., & Noppe, L. D. (1991). Human development across the life span. Merrill.

Cita Chicago (17th ed.)

Hughes, Fergus P., i Lloyd D. Noppe. Human Development Across the Life Span. New York: Merrill, 1991.

Cita MLA (9th ed.)

Hughes, Fergus P., i Lloyd D. Noppe. Human Development Across the Life Span. Merrill, 1991.