APA (7th ed.) Citation

Campbell, R. L., & Bickhard, M. H. (1986). Knowing levels and developmental stages. Karger.

Chicago Style (17th ed.) Citation

Campbell, Robert L., and Mark H. Bickhard. Knowing Levels and Developmental Stages. Basel ; New York: Karger, 1986.

MLA (9th ed.) Citation

Campbell, Robert L., and Mark H. Bickhard. Knowing Levels and Developmental Stages. Karger, 1986.