1. Keeler, S.P. and Backofen, W.A., “Plastic Instability and Fracture in Sheets Stretched Over Rigid Punches”, Trans. ASM, 56 (1963), 25–48.
2. Keeler, S.P., “Determination of Forming Limits in Automotive Stampings”, Sheet Metal Ind., 42 (1965), 683–91.
3. American Deep Drawing Research Group, “Analysis of Sheet Metal Formability”, in Sheet Metal Forming and Formability, Proceedings of 7th Biennial Congress of the International Deep Drawing Research Group, Amsterdam (1972), 18.1–18.7.
4. Keeler, S.P., “Circular Grid System–A Valuable Aid for Evaluating Sheet Metal Formability”, SAE Paper No. 680092 (1968), 1–9.
5. Goodwin, G.M., “Application of Strain Analysis to Sheet Metal Forming Problems in the Press Shop”, SAE Paper No. 680093 (1968), 1–12.