Bess, James L., author
Jossey-Bass, 2000
Buku Teks
Hammonds, Carsie, 1894-, author
Mcgraw-Hill , 1950
Buku Teks
S. Venkataiah, editor
Anmol Publications, 2001
Buku Teks
Anmol Publications PVT, 2001
Buku Teks
Peters, Herman Jacob, 1917-, author
Macmillan, 1963
Buku Teks