Wilhelm Fink, 1971
Buku Teks
Waerden, B. L. van der
New York Frederick Ungar Publishing Co. 1943,
Buku Teks
Maus, Heinz
Ferdinand Enke, 1962
Buku Teks
Harberts, DW
Amsterdam Meulenhoff 1948
Buku Teks
Frost, Walter
Munchen Verlag Ernst Reinhardt 1926
Buku Teks