Newall, Christopher
Phaidon, c1987
Buku Teks SO
edited by E.K. Brown
Thomas Nelson and Sons, 1942
Buku Teks SO
Adams, James E.
Wiley-Blackwell, 2009
Buku Teks
edited by Patrick Brantlinger and William B. Thesing
Blackwell, 2002
Buku Referensi
edited by William Frost
Prentice-Hall, 1952
Buku Teks SO