Walsh, F. K., & Halliday, W. R. (1971). Discovery and exploration of the Oregon caves: Oregon Caves National Monument. Te-Cum-Tom Enterprises.
Cita Chicago Style (17a ed.)Walsh, Frank K., y William R. Halliday. Discovery and Exploration of the Oregon Caves: Oregon Caves National Monument. [Grants Pass, Or.: Te-Cum-Tom Enterprises, 1971.
Cita MLA (8a ed.)Walsh, Frank K., y William R. Halliday. Discovery and Exploration of the Oregon Caves: Oregon Caves National Monument. Te-Cum-Tom Enterprises, 1971.
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