Drooyan, Irving
Elementary algebra : structure and skills
John Wiley & Sons, 1981
 Buku Teks SO
Heinemann atlas 2
Heinemann Educational Books, 1986
 Buku Referensi
Hearing, Sylvia, 1954-
Computerized accounting : an integrated skills approach / Sylvia Hearing
Regents/Prentice Hall, 1994
 Buku Teks SO
Alexander, L.G.
Developing skills : an integrated course for intermediate students
Longman, 1964
 Buku Teks SO
Callow, Duncan
Wheels of justice the motorist`s guide to the law / Duncan Callow
Chischester, 1995
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