found: His Lectures on minimal models, c1983:t.p. (S. Halperin) p. 6 (University of Toronto)
found: LC data base, 1-14-85(hdg.: Halperin, Stephen; usage: Stephen Halperin) LC manual auth. cd. (Halperin, Stephen, Dept. of Mathematics, Univ. of Toronto)
found: Rational homotopy theory II, 2015:ECIP t.p. (Steve Halperin; University of Maryland)
found: University of Maryland, Mathematics department, viewed Dec. 1, 2014(Steve Halperin; professor of mathematics, and director of the Climate Information Responding to User Needs (CIRUN) initiative at the University of Maryland; previously, he was professor and chair in the Department of Mathematics at the University of Toronto)