@incollection{AST_1977__50__293_0,
     author = {Medved, M.},
     title = {On generic bifurcations of second order ordinary differential equations near closed orbits},
     booktitle = {Syst\`emes dynamiques II - Varsovie},
     series = {Ast\'erisque},
     pages = {293--297},
     publisher = {Soci\'et\'e math\'ematique de France},
     number = {50},
     year = {1977},
     mrnumber = {494279},
     zbl = {0387.58005},
     language = {en},
     url = {http://www.numdam.org/item/AST_1977__50__293_0/}
}