Kaligis, O.C. (Otto Cornelis), 1942-, author
O.C. Kaligis & Associates, 2004
Buku Teks
Hiariej, Eddy O.S., 1973-, author
Erlagga, 2010
Buku Teks
Mathias, Peter
Methuen , 1979
Buku Teks
Gultom, Erikson Hasiholan, author
Tatanusa, 2006
Buku Teks
Schmid, Evelyne, author
Cambridge University Press, 2015
Buku Teks