Johnson, K., & Herr, T. (2001). Problem solving strategies: Crossing the river with dogs : and other mathematical adventures (2nd ed.). Key Curriculum Press.
Цитирование в стиле Чикаго (17-е изд.)Johnson, Ken, и Ted Herr. Problem Solving Strategies: Crossing the River with Dogs : And Other Mathematical Adventures. 2nd ed. Emeryville, Calif: Key Curriculum Press, 2001.
Цитирование MLA (9-е изд.)Johnson, Ken, и Ted Herr. Problem Solving Strategies: Crossing the River with Dogs : And Other Mathematical Adventures. 2nd ed. Key Curriculum Press, 2001.
Предупреждение: эти цитированмия не могут быть всегда правильны на 100%.