Kaiser, Edward John, author
Buku Teks
Kaiser, Edward John, author
University of Illinois Press, 1995
Buku Teks
Chusnul Mar`iyah, author
1998
Artikel Jurnal
Marsh, William M., author
McGraw-Hill, 1978
Buku Teks
Barlowe, Raleigh, author
Prentice-Hall, 1961
Buku Teks