John, Yun, author
Hongikmedia, 2007
Buku Referensi
Yun, Jo
Hongik Media, 2007
Buku Teks
Haywood, Roger, 1939-, author
McGraw-Hill , 1984
Buku Teks
Gerling, Heinrich, author
Wiley Eastern Limited, 1982
Buku Teks
Farrant, Natasha, author
Faber and Faber, 2015
Buku Teks