Subject:"Helferich, Peter C. (SC'1960)" Remove Publication Year:"1970" Remove Publication Year:"1970" Remove Publication:"Purdue Alumnus" Remove Subject:"Helferich, Peter C. (SC'1960)" Remove Subject:"Helferich, Peter C. (SC'1960)" Remove Publication:"Purdue Alumnus" Remove Subject:"Helferich, Peter C. (SC'1960)" Remove