Pumice, pumicite, and volcanic cinders in California, by Charles W. Chesterman, and Technology of pumice, pumicite, and volcanic cinders, by F. Sommer Schmidt. (California. Division of Mines. Bulletin, 174)
Pumice, pumicite, and volcanic cinders in California, by Charles W. Chesterman, and Technology of pumice, pumicite, and volcanic cinders, by F. Sommer Schmidt.