Spring, I., & Manning, H. (1974). Wilderness trails Northwest: A hiker's and climber's overview-guide to national parks and wilderness areas in Wyoming, Montana, Idaho, Northern California, Oregon, Washington, British Columbia, Canadian Rockies. Touchstone Press.
Style de citation Chicago (17e éd.)Spring, Ira, et Harvey Manning. Wilderness Trails Northwest: A Hiker's and Climber's Overview-guide to National Parks and Wilderness Areas in Wyoming, Montana, Idaho, Northern California, Oregon, Washington, British Columbia, Canadian Rockies. Beaverton, Or.: Touchstone Press, 1974.
Style de citation MLA (8e éd.)Spring, Ira, et Harvey Manning. Wilderness Trails Northwest: A Hiker's and Climber's Overview-guide to National Parks and Wilderness Areas in Wyoming, Montana, Idaho, Northern California, Oregon, Washington, British Columbia, Canadian Rockies. Touchstone Press, 1974.