1. The stone skeleton;Heyman;Int J Solids Struct,1966
2. The safety of masonry arches;Heyman;Int J Solids Struct,1969
3. The masonry arch;Heyman,1982
4. The stone skeleton;Heyman,1995
5. Orduna A, Lourenco PB. Limit analysis as a tool for the simplified assessment of ancient masonry structures. In: Proc III SAHC, Guimares; 2001.