Downie, N., & Heath, R. W. (1970). Basic statistical methods (3rd ed.). Harper & Row.
Lua i Stíl Chicago (17ú heag.)Downie, N.M, agus R. W. Heath. Basic Statistical Methods. 3rd ed. New York: Harper & Row, 1970.
Lua MLA (9ú heag.)Downie, N.M, agus R. W. Heath. Basic Statistical Methods. 3rd ed. Harper & Row, 1970.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.