Helmus, T. M., & Arnsdorf, V. E. (1984). The United States and its neighbors. Silver Burdett.
Chicago Style (17th ed.) CitationHelmus, Timothy M., and Val E. Arnsdorf. The United States and Its Neighbors. Morristown, NJ [u.a.]: Silver Burdett, 1984.
MLA (9th ed.) CitationHelmus, Timothy M., and Val E. Arnsdorf. The United States and Its Neighbors. Silver Burdett, 1984.
Warning: These citations may not always be 100% accurate.