@incollection{AST_1980__75-76__105_0,
     author = {Fornasini, E.},
     title = {Research topics in linear systems on partially ordered time sets},
     booktitle = {Analyse des syst\`emes},
     series = {Ast\'erisque},
     pages = {105--114},
     publisher = {Soci\'et\'e math\'ematique de France},
     number = {75-76},
     year = {1980},
     mrnumber = {581707},
     zbl = {0458.93026},
     language = {en},
     url = {http://archive.numdam.org/item/AST_1980__75-76__105_0/}
}