Laing, R.D.
McGraw-Hill, 1985
Buku Teks
Fisher, Dorothy Canfield
Whittlesey House McGraw-Hill Book Coy Inc, 1959
Buku Teks
Cummings, Paul, author
St. Martin's Press, 1966
Buku Referensi
Fielding, Mantle, 1865-1941, author
Apollo, 1983
Buku Referensi
Illinois USA, 1974
Buku Referensi