APA (7th ed.) Citation

National Science Teachers Association & Gabel, D. (1989). Problem solving. National Science Teachers Association.

Chicago Style (17th ed.) Citation

National Science Teachers Association and Dorothy Gabel. Problem Solving. Washington, D.C.: National Science Teachers Association, 1989.

MLA (9th ed.) Citation

National Science Teachers Association and Dorothy Gabel. Problem Solving. National Science Teachers Association, 1989.

Warning: These citations may not always be 100% accurate.