Gallas, K. R., author
J. B. Wolters, [date of publication not identified]
Buku Referensi
Herckenrath, C. R. C., author
J. B. Wolters U. M., [date of publication not identified]
Buku Referensi
Elout, C. P. J., author
Johannes Enschede en Zonen, 1825
Buku Referensi
Wely, van Prick
G.B Van Goor Zonen's U.M N.V , 1927
Buku Teks
Vries, Jan de, author
Het Spectrum, 1991
Buku Teks