Williams, Homer L., author
Wiley , 2010
Buku Teks
Fraser, Cynthia, author
Springer, 2012
eBooks
Kohlmaier, Georg, author
MIT Press, 1986
Buku Teks
Edson, Gary, author
Routledge, 1996
Buku Referensi
edited by Ulla Keding Olofsson ; illustrator, Teichert, Gerard
Unesco , 1979
Buku Teks