1. Thoft-Christensen, P.: The ß-unzipping method. Institute of Building Technology and Structural Engineering, Aalborg University Centre, Aalborg, Report 8207, 1982 (not published).
2. Thoft-Christensen, P. & Sorensen, J. D.: Calculation of Failure Probabilities of Ductile Structures by the ß-unzipping Method. Institute of Building Technology and Structural Engineering, Aalborg University Centre, Aalborg, Report 8208, 1982.
3. Thoft-Christensen, P. & Sorensen, J. D.: Reliability Analysis of Elasto-Plastic Structures. Proc. 11. IFIP Conf. »System Modelling and Optimization», Copenhagen, July 1983. Springer-Verlag, 1984, pp. 556–566.
4. Rackwitz, R. & Fiessler, B.: An Algorithm for Calculation of Structural Reliability under Combined Loading. Berichte zur Sicherheitstheorie der Bauwerke, Lab. f. Konstr. Ingb., Techn. Univ. München, München, 1977.
5. Thoft-Christensen, P. & Baker, M. J.: Structural Reliability and Its Applications. Springer-Verlag, Berlin-Heidelberg-New York, 1982.