Chidsey, Donald Barr
Crown, 1958
Buku Teks
Hall, Robert T.
Harper and Row, 1971
Buku Teks
Hall, Ford P.
McGraw-Hill Book Company , 1949
Buku Teks
Abrahamsen, Martin A., author
McGraw-Hill Book , 1976
Buku Teks
Monsen, R. Joseph
McGraw-Hill, 1965
Buku Teks