Greg Byrd; Lynn Byrd; Chris Pearce. (2012). Cambridge Checkpoint Mathematics Coursebook 7 (Cambridge International Examinations). CAMBRIDGE UNIVERSITY PRESS.
Chicago-viite (17. p.)Greg Byrd; Lynn Byrd; Chris Pearce. Cambridge Checkpoint Mathematics Coursebook 7 (Cambridge International Examinations). CAMBRIDGE UNIVERSITY PRESS, 2012.
MLA-viite (9. p.)Greg Byrd; Lynn Byrd; Chris Pearce. Cambridge Checkpoint Mathematics Coursebook 7 (Cambridge International Examinations). CAMBRIDGE UNIVERSITY PRESS, 2012.
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