Ha, Tae Hung
Yonsei University Press, 1958
Buku Teks SO
Harman, Carter
Dell Publishing, 1956
Buku Teks
Schleifer, Ronald
Cambridge University Press, 2011
eBooks
Andy Bennett, Steve Waksman
SAGE, 2015
Buku Teks SO
Ha, Tae Hung
Yonsei University Press, 1984
Buku Teks