Williams, C. (1980). Bridge of the gods, mountains of fire: A return to the Columbia Gorge. Friends of the Earth ; Elephant Mountain Arts.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रWilliams, Chuck. Bridge of the Gods, Mountains of Fire: A Return to the Columbia Gorge. New York : White Salmon, [Wash.]: Friends of the Earth ; Elephant Mountain Arts, 1980.
एमएलए (8वां संस्करण) प्रशस्ति पत्रWilliams, Chuck. Bridge of the Gods, Mountains of Fire: A Return to the Columbia Gorge. Friends of the Earth ; Elephant Mountain Arts, 1980.
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