References
- Carin , Arthur and Sund , Robert. 1971 . Developing Questioning Techniques: A Self-Concept Approach , Columbus , Ohio : Merrill .
- Piltz , Albert and Sund , Robert. 1974 . Creative Teaching of Science in the Elementary School , 2d ed. , Boston : Allyn and Bacon .
- Shulene , John. 1972 . “Inquiry-oriented Pictorial Riddles in Science for Educable Mentally Handicapped Children.” University of Northern Colorado Unpublished Doctor of Education dissertation