Dake, H. C. (1962). Northwest gem trails: A field guide for the gem hunter, mineral collector, and tourist, covering both popular and little known areas of Oregon, Washington, Idaho, British Columbia (3d ed. completely rev.). Gembooks.
Trích dẫn kiểu Chicago (xuất bản lần thứ 7)Dake, H. C. Northwest Gem Trails: A Field Guide for the Gem Hunter, Mineral Collector, and Tourist, Covering Both Popular and Little Known Areas of Oregon, Washington, Idaho, British Columbia. 3d ed. completely rev. Mentone, Calif.: Gembooks, 1962.
Trích dẫn kiểu MLA (xuất bản lần thứ 8)Dake, H. C. Northwest Gem Trails: A Field Guide for the Gem Hunter, Mineral Collector, and Tourist, Covering Both Popular and Little Known Areas of Oregon, Washington, Idaho, British Columbia. 3d ed. completely rev. Gembooks, 1962.
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