Nassau, Kurt
John Wiley & Sons, 1983
Buku Teks
Back, Kurt W., author
John Wiley & Sons, 1977
Buku Teks
Grimm, Wilhem
Bonn: Dummlers, 1960
Buku Teks
London, Kurt, editor
D.van Nostrand Company,Inc., 1950
Buku Teks
Pearson, Jean E.
Peter Lang, 1992
Buku Teks