@article{MSH_1992__117__49_0,
     author = {Thiopoulos, Constantin},
     title = {Towards a logic of semiotic systems},
     journal = {Math\'ematiques informatique et sciences humaines},
     pages = {49--60},
     publisher = {Ecole des hautes-\'etudes en sciences sociales},
     volume = {117},
     year = {1992},
     mrnumber = {1164608},
     zbl = {0846.68065},
     language = {en},
     url = {http://archive.numdam.org/item/MSH_1992__117__49_0/}
}