Balcı, Hasan. Problemler dünyası : İlköğretim 2 / by Hasan Balcı, Edip San and Perihan Cengiz. - İstanbul : Mutlu, 2006. - 176 p. : col., ill ; 28 cm. Includes CDROM. K-3. Turkish. ISBN: 9755864415 Subjects--Topical Terms: Mathematics--Study and teaching--Grade 2.