Whitehead, Alfred North, 1861-1947, author
The New American Library, 1933
Buku Teks
Gallup, George, author
McGraw-Hill, 1982
Buku Teks
edited by Matthew Beaumont
Blackwell, 2007
Buku Teks
Moser, A. P., author
McGraw-Hill, 2001
Buku Teks
Won-young, Kim ; Hwi-joon, Ahn ; Lena, Kim ; Byong-sam, Han ; Yang-mo, Chung ; edited by. Whitfield, Roderick ; Young-sook, Pak
Jebyong Publications , 1986
Buku Referensi