Kers, Martin, 1944-, author
Terra Zutphen, 1988
Buku Referensi
Pet, Paul C., author
Elmar, 1994
Buku Referensi
Brugmans, H., author
Scheltema & Holkema`s, [Date of publication not identified]
Buku Teks
Kers, Marijke
Bv Laren, 1984
Buku Referensi
Foreign Languages Publishing House , 1960
Buku Teks