APA (7th ed.) Citation

Helmus, T. M., & Arnsdorf, V. E. (1984). The United States and its neighbors. Silver Burdett.

Chicago Style (17th ed.) Citation

Helmus, Timothy M., and Val E. Arnsdorf. The United States and Its Neighbors. Morristown, NJ [u.a.]: Silver Burdett, 1984.

MLA (9th ed.) Citation

Helmus, Timothy M., and Val E. Arnsdorf. The United States and Its Neighbors. Silver Burdett, 1984.