1. Implications of the Rhodesia age pattern;Ahrens;Geochim. et Cosmochim. Acta,1955
2. New developments in the production and measurement of ultra-high vacuum;Alpert;J. Appl. Phys.,1953
3. The determinations of sodium and potassium in silicate rocks by flame photometer;Brannock;U.S. Geol. Survey Bull.,1949
4. The granitic rocks of the Yosemite region;Calkins;U.S. Geol. Survey, Professional Paper,1930
5. Palaeontological correlation of Elk Point and equivalents;Crickmay,1954