by Belverd E. Needles ... [and others]
Houghton Miffiln, 1999
Buku Teks
Slavin, Albert
Holt Rinehart and Winston, 1972
Buku Teks
Warren, Carl S.
International Thomson, 1999
Buku Teks
Reeve, James M., 1953-
South Western Cengage Learning, 2012
Buku Teks
Warren, Carl S.
Thomson, 2005
Buku Teks