Gup, Benton E.
John Wiley & Sons, 1987
Buku Teks SO
Weston, John Fred, 1916-
Dow Jones/Irwin, 1982
Buku Teks
Riggs, James L.
McGraw-Hill, 1974
Buku Teks
Weetman, Pauline
Prentice Hall, 2003
Buku Teks
Henderson, Glenn V.
[Publisher not identified], [Date of publication not identified]
Buku Teks