00836cam a22002651 4500 gs 53000085 DLC 20260227111359.0 850617s1952 dcua b f000 0 eng c gs 53000085 (OCoLC)12166396 U. S. Geol. Survey. Libr. TxHR TxHR DLC premarc QE75 .C5 no. 225 553.49 Fleischer, Michael, 1908- Geochemical association of niobium (columbium) and titanium and its geological and economic significance, by Michael Fleischer [and others] Washington, 1952. 13 p. tables. 27 cm. Geological Survey circular 225 Erratum slip inserted. "Literature cited": p. 9-10. Niobium. Titanium. 28718 28718