Ben-Chai, David, author
Sense, 2012
eBooks
Devine, Donald F., author
John Wiley & Sons, 1977
Buku Teks
Ralph Crouch
J. Wiley , 1965
Buku Teks
Long, Calvin T., author
Pearson - Addison Wesley, 2009
Buku Teks
Connelly, James F., author
Macmillan, 1978
Buku Teks