Lohr, S. . L. (1999). Sampling design and analysis. Duxbury Press.
Lua i Stíl Chicago (17ú heag.)Lohr, Sharon L. Sampling Design and Analysis. Pacific Grove, Calif: Duxbury Press, 1999.
Lua MLA (9ú heag.)Lohr, Sharon L. Sampling Design and Analysis. Duxbury Press, 1999.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.