O`Hagan, Andrew, 1968-, author
Houghton Mifflin Harcourt, 2013
Buku Teks
Peterson, Roger Tory, author
Houghton Miffiln, 1980
Buku Referensi
Khutsishvili, G
Progress, 1980
Buku Teks
Drotning, Phillip T., author
Doubleday, 1968
Buku Teks
Dolbegae Publishers, 2007
Buku Referensi