edited by Magie Toy
Academy Editions, 1995
Buku Teks
Sinaga, Reynhard Tambos Maruli Tua, author
Fakultas Teknik Universitas Indonesia, 2006
UI - Skripsi (Membership)
Vale, Lawrence J., author
Routledge, 2008
Buku Teks
edited by Peter Cook, Nell Spiller
Academic Edition, 1999
Buku Teks
Hill, Jonathan, 1958- author
Routledge, 2012
Buku Teks