1. Plastic instability and fracture in sheets stretched over rigid punches;Keeler,1961
2. Circular grid system: a valuable aid for evaluating sheet metal formability, SAE Technical Paper 680092;Keeler,1965
3. Application of strain analysis to sheet metal forming problems in the press shop, SAE Technical Paper 680093;Goodwin,1968
4. Technology for using sheet steel – designing for formability;Chatfiel;Met Prog,1971
5. Forming-limit criteria-sheets;Keeler,1974