Leypoldt, M. M. (1971). Learning is change. Judson Press.
Lua i Stíl Chicago (17ú heag.)Leypoldt, Martha M. Learning Is Change. Valley Forge, Pa.: Judson Press, 1971.
Lua MLA (8ú heag.)Leypoldt, Martha M. Learning Is Change. Judson Press, 1971.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.