Mellersh, H.E.L., author
Simon & Schuster, 1994
Buku Referensi
Hall, Jonathan M., auhtor
Wiley-Blackwell, 2014
Buku Teks
Lensen, George Alexander
Charles E. Tuttle Co., 1970
Buku Teks
Salmon, Edward T., author
Routledge, 1995
Buku Teks
Berry, George Ricker, author
Chicago, Fallet Publishing, 1962
Buku Referensi