@article{ITA_1983__17_2_163_0, author = {Janssens, D. and Rozenberg, G.}, title = {Hypergraph systems and their extensions}, journal = {RAIRO. Informatique th\'eorique}, pages = {163--196}, publisher = {EDP-Sciences}, volume = {17}, number = {2}, year = {1983}, mrnumber = {713228}, zbl = {0512.68062}, language = {en}, url = {http://www.numdam.org/item/ITA_1983__17_2_163_0/} }