@article{BUMI_2005_8_8B_2_a2,
     author = {Cellina, Arrigo},
     title = {The {Euler} {Lagrange} {Equation} and the {Pontriagin} {Maximum} {Principle}},
     journal = {Bollettino della Unione matematica italiana},
     pages = {323--347},
     publisher = {mathdoc},
     volume = {Ser. 8, 8B},
     number = {2},
     year = {2005},
     zbl = {1178.49021},
     mrnumber = {801585},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/BUMI_2005_8_8B_2_a2/}
}