Walsh, Myles E., author
John Wiley & Sons, 1981
Buku Teks
Frieman, Barry B., author
McGraw-Hill, 2001
Buku Teks
Harderer, Michael, author
OPEC Secretariat, 2011
Buku Referensi
DePamphilis, Donald, author
Elsevier , 2011
Buku Teks
Stebben, Gregg, author
Pocket Books, 1999
Buku Referensi