Foreign Languages Publishing House, 1960
Buku Teks SO
Kers, Martin, 1944-
Terra Zutphen, 1988
Buku Referensi
edited by William M. Sale
Holt, Rinehart and Winston, 1961
Buku Teks SO
Christophe Champod [and others]
CRC Press, 2004
Buku Teks
Kers, Martin, 1944-
Bv Laren, 1984
Buku Referensi