Schoene, B., and S.A. Bowring. (2006) 2006. “U–Pb Systematics of the McClure Mountain Syenite: Thermochronological Constraints on the Age of the 40Ar 39Ar Standard MMhb”. Contributions to Mineralogy and Petrology 151 (5): 615-30. doi:10.1007/s00410-006-0077-4.