APA
Hanson R. D., Degenkolb H. J., . (1969). The Venezuela earthquake : july 29, 1967. New York: American Iron and Steel Institute.
Chicago
Hanson Robert D, Degenkolb Henry J, . 1969. The Venezuela earthquake : july 29, 1967. New York: American Iron and Steel Institute.
Harvard
Hanson R. D., Degenkolb H. J., . (1969). The Venezuela earthquake : july 29, 1967. New York: American Iron and Steel Institute.
MLA
Hanson Robert D, Degenkolb Henry J, . The Venezuela earthquake : july 29, 1967. New York: American Iron and Steel Institute. 1969.