1. An Inequality for the Angle Measure in a Triangle;Barrett;Journal of Mathematical Behavior,1989
2. Understanding area;Biggs;Journal of Mathematical Behavior,1987
3. Rapid changes seen in young brain;Blakeslee;New York Times,1986
4. A collection of math lessons from grades 1 through 3;Burns,1988
5. Child-created mathematics;Cochran;Arithmetic Teacher,1970