@article{MS2_1975__36_166407,
     author = {R.Tyrell Rockafellar},
     title = {Semigroups of convex bifunctions generated by {Lagrange} problems in the calculus of variations.},
     journal = {Mathematica Scandinavica},
     pages = {138--159},
     year = {1975},
     volume = {36},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/MS2_1975__36_166407/}
}