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2. Core softening in cavernously weathered tonalite;Conca;J. Geol.,1985
3. Field assessment of rock hardness using the Schmidt test hammer;Day;British Geomorphic Research Group Technical Bulletin No. 18,1977
4. Quaternary glaciation and tectonism in the southeastern Sierra Nevada, Inyo County, California;Gillespie,1982
5. Resistance of transparent plastics to surface abrasion,1979