Leipziger, D. M. (1981). Basic needs and development. Oelgeschlager, Gunn & Hain.
Lua i Stíl Chicago (17ú heag.)Leipziger, Danny M. Basic Needs and Development. Cambridge, Mass: Oelgeschlager, Gunn & Hain, 1981.
Lua MLA (9ú heag.)Leipziger, Danny M. Basic Needs and Development. Oelgeschlager, Gunn & Hain, 1981.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.