Song, Nak-won, author
Communication Books (Ju), 2008
Buku Teks
Phelps, Guy
Victor Gollanez, 1975
Buku Teks
Budi Irawanto, author
Media Pressindo, 1999
Buku Teks
Phelps, Guy
Victor Gollanez, 1975
Buku Teks
Musser, Charles, author
Macmillan Library reference USA,, 1990
Buku Referensi