@article{SEDP_1983-1984____A20_0,
     author = {Lions, J-L.},
     title = {Sur le contr\^ole ponctuel de syst\`emes hyperboliques ou du type {Petrowski}},
     journal = {S\'eminaire \'Equations aux d\'eriv\'ees partielles (Polytechnique) dit aussi "S\'eminaire Goulaouic-Schwartz"},
     note = {talk:20},
     pages = {1--20},
     publisher = {Ecole Polytechnique, Centre de Math\'ematiques},
     year = {1983-1984},
     mrnumber = {811663},
     zbl = {0549.49018},
     language = {fr},
     url = {http://www.numdam.org/item/SEDP_1983-1984____A20_0/}
}