Empat untuk buku bulan ini http://180.210.203.191/images/getimage.aspx?ean=9780613922678&isbn=0613922670&size=BIG http://180.210.203.191/images/getimage.aspx?ean=9780345431912&isbn=034543191X&size=BIG http://180.210.203.191/images/getimage.aspx?ean=9780486447407&isbn=048644740