by George Zis ... [et al.]
Longman, 1988
Buku Teks SO
Salvatore, Dominick
Prentice-Hall, 1998
Buku Teks SO
Salvatore, Dominick
Macmillan, 1993
Buku Teks SO
Walter, Ingo
John Wiley & Sons, 1981
Buku Teks SO
Salvatore, Dominick
John Wiley & Sons, 2007
Buku Teks SO