Literature

• E. Happold and W. I. Liddell, “Timber lattice roof for the Mannheim Bundesgartenschau,” The Structural Engineer, vol. 53, no. 3, pp. 99–135, 1975
• I. Liddell, “Frei Otto and the development of gridshells,” Case Studies in Structural Engineering, vol. 4, no. Supplement C, pp. 39–49, 2015