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
Andreae, S.J. Fockema, author
Groningen, 1951
Buku Teks
Andreae, S.J. Fockema, author
Groningen, 1948
Buku Teks
Koenen, Matthijs Jacobus, 1847-, author
J.B. Wolters Uitgeversmaatschappij, [Date of publication not identified]
Buku Referensi