Harris, Jonathan, author
Wiley Blackwell, 2017
Buku Teks
Kaufman, Irving, author
Macmillan, 1966
Buku Teks
Barrett, Terry, 1945-, author
McGraw-Hill, 2012
Buku Teks
Yekyong Publications, 1987
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