Mcdonald, Brian Thomas
John Wiley & Sons, 2006
Buku Teks SO
Smith, Stephen W.
John Wiley & Sons, 1997
Buku Teks
Holden, Robert
Laurence King Publishing, 1996
Buku Referensi
Eckbo, Garrett
McGraw-Hill, 1964
Buku Teks SO
Munson, Albe E.
McGraw-Hill, 1974
Buku Teks