Magee, John H.
Richard D. Irwin, 1951
Buku Teks
Ingrisano, John R., author
Chicago, Dearborn Financial Publishing, 1990
Buku Referensi
R & R Newkirk/Longman, 1985
Buku Referensi
Zaccaro, Gianluca, author
Academic , 2011
Buku Teks
Poh Chu Chai
Butterworth, 1999
Buku Teks