Baxter, C. H. b. 1., Parks, R. D. 1., Whitehead, W. L. b. 1., & Pardee, F. G. b. 1. (1957). Examination and valuation of mineral property (4th ed.). Massachusetts: Addison-Wesley Pub Co..
Παραπομπή Chicago StyleBaxter, Charles H. b. 1879, Roland D. 1900- Parks, Walter L. b. 1891 Whitehead, and Franklin G. b. 1891 Pardee. Examination and Valuation of Mineral Property. 4th ed. Massachusetts: Addison-Wesley Pub Co., 1957.
Παραπομπή MLABaxter, Charles H. b. 1879, Roland D. 1900- Parks, Walter L. b. 1891 Whitehead, and Franklin G. b. 1891 Pardee. Examination and Valuation of Mineral Property. 4th ed. Massachusetts: Addison-Wesley Pub Co., 1957.
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