Ross, H. Laurence (Hugh Laurence), author
McGraw-Hill, 1973
Buku Teks
Bell, Earl H.
Harper & Row, 1965
Buku Teks
Appleton-Century-Crofts , 1967
Buku Teks
Schrag, Clarence C., author
Harper & Row, 1963
Buku Teks
Zanden, James W. Vander, author
John Wiley & Sons, 1979
Buku Teks