Oregon. Department of Geology and Mineral Industries, Southern Oregon Title Guaranty & Abstract Co, Preston, R. N., Preston, M. L., Cram, G. F., & Miller, C. N. (2000). Oregon gold/silver & gems maps, then and now: Gold/silver, agate, apache tears, bloodstone ... thunder eggs, tourmaline, jade. R.N./M.L. Preston.
توثيق أسلوب شيكاغو (الطبعة السابعة عشر)Oregon. Department of Geology and Mineral Industries, Southern Oregon Title Guaranty & Abstract Co, Ralph N. Preston, M. L. Preston, George Franklin Cram, و C. N. Miller. Oregon Gold/silver & Gems Maps, Then and Now: Gold/silver, Agate, Apache Tears, Bloodstone ... Thunder Eggs, Tourmaline, Jade. [S.l.]: R.N./M.L. Preston, 2000.
توثيق جمعية اللغة المعاصرة MLA (الطبعة الثامنة)Oregon. Department of Geology and Mineral Industries, et al. Oregon Gold/silver & Gems Maps, Then and Now: Gold/silver, Agate, Apache Tears, Bloodstone ... Thunder Eggs, Tourmaline, Jade. R.N./M.L. Preston, 2000.