Kail V. Robert & Rita Wicks- Nelson. (1993). Development Psychology (5th ed.). Prentice-Hall..
Lua i Stíl Chicago (17ú heag.)Kail V. Robert agus Rita Wicks- Nelson. Development Psychology. 5th ed. New Jersey: Prentice-Hall., 1993.
Lua MLA (9ú heag.)Kail V. Robert agus Rita Wicks- Nelson. Development Psychology. 5th ed. Prentice-Hall., 1993.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.