Head, Thomas C.
Houghton Miffiln, 1986
Buku Teks
Herbert, Theodore T.
Macmillan, 1976
Buku Teks
Knudson, Harry R., editor
SAddison-Wesley Pub. Co., 1967
Buku Teks
Dittrich, John E.
Business Publ. Inc., 1981
Buku Teks
Lovelock, Christopher H.
McGraw-Hill, 1985
Buku Teks