Kurtz, Max
McGraw-Hill, 1969
Buku Teks
Underwood, James R., author
Wiley, 2007
Buku Teks
Underwood, James R., author
John Wiley & Sons, 1998
Buku Referensi
Underwood, Rod
John Wiley & Sons, 2007
Buku Teks
Underwood, James R., author
John Wiley, 1998.
Buku Teks