APA (7th ed.) Citation

Engelhardt, J. M., Ashlock, R. B., & Wiebe, J. H. (1984). Helping children understand and use numerals. Allyn and Bacon.

Chicago Style (17th ed.) Citation

Engelhardt, Jon M., Robert B. Ashlock, and James H. Wiebe. Helping Children Understand and Use Numerals. Boston: Allyn and Bacon, 1984.

MLA (8th ed.) Citation

Engelhardt, Jon M., et al. Helping Children Understand and Use Numerals. Allyn and Bacon, 1984.