Fishman, Joshua A., author
Newbury House Publishers, 1972
Buku Teks
The Hague, 1972
Buku Teks
edited by Ulrich Ammon, Norbert Dittmar, Klaus J. Mattheier
Walter de Gruyter, 1987
Buku Referensi
edited by Ulrich Ammon, Norbert Dittmar, Klaus J. Mattheier
Walter de Gruyter, 1988
Buku Referensi
Malmstrom, Jean, author
Hayden Book Company, 1965
Buku Teks