Artikel Jurnal
by Arthur I. Gates [and others]
Macmillan, 1962
Buku Teks
Hoy, Anita Woolfolk, 1947-, author
Allyn and Bacon, 2004
Buku Teks
edited by Robert L. Linn ; sponsored jointly by National Council on Measurement in Education and American Council on Education
New York, 1989
Buku Teks
Preager, 1976
Buku Teks