Eggleston, De Witt C.
Chapman & Hall Ltd. , 1926
Buku Teks
Lee Harrison, editor in chief
McGraw-Hill, 1995
Buku Referensi
edited by Lee Harrison
McGraw-Hill, 1997
Buku Referensi
Carlson, Ronald L., author
Anderson, 1970
Buku Teks
Ranz, John H.
W.H. Anderson Co., 1966
Buku Teks