Geological Survey (U.S.). (1953). Interpreting geologic maps for engineering purposes: Hollidaysburg quadrangle, Pennsylvania.
Citación estilo ChicagoGeological Survey (U.S.). Interpreting Geologic Maps for Engineering Purposes: Hollidaysburg Quadrangle, Pennsylvania. Washington, 1953.
Cita MLAGeological Survey (U.S.). Interpreting Geologic Maps for Engineering Purposes: Hollidaysburg Quadrangle, Pennsylvania. 1953.
Warning: These citations may not always be 100% accurate.