Encyclopedia of educational research : sixth edition, volume 1
Marvin C. Alkin, editor-in-chief
MacMillan Library Reference USA, 1992
 Buku Referensi
Encyclopedia of educational research; Volume 1
editor-in-chief, Harold E. Mitzel
Free Press, 1993
 Buku Referensi
Novick, Melvin R.
Statistical methods for educational and psychological research / Melvin R. Novick and Paul H. Jackson
McGraw-Hill, 1974
 Buku Teks
Encyclopedia of educational research; Volume 2
editor-in-chief, Harold E. Mitzel
Free Press, 1993
 Buku Referensi
Encyclopedia of educational research; Volume 3
editor-in-chief, Harold E. Mitzel
Free Press, 1993
 Buku Referensi