@article{RSMUP_1990__83__19_0,
     author = {Mirenghi, Elvira and Tucci, Maria},
     title = {Existence of $T$-periodic solutions for a class of lagrangian systems},
     journal = {Rendiconti del Seminario Matematico della Universit\`a di Padova},
     pages = {19--32},
     publisher = {Seminario Matematico of the University of Padua},
     volume = {83},
     year = {1990},
     mrnumber = {1066425},
     zbl = {0709.34034},
     language = {en},
     url = {http://www.numdam.org/item/RSMUP_1990__83__19_0/}
}