@article{MAN_1983__263_163749,
     author = {A.J. Tromba},
     title = {A {Sufflcient} {Condition} for a {Critical} {Point} of a {Functional} to be a {Minimum} and {Its} {Application} to {Plateau'} s {Problem.}},
     journal = {Mathematische Annalen},
     pages = {303--312},
     publisher = {mathdoc},
     volume = {263},
     year = {1983},
     zbl = {0518.58012},
     url = {http://geodesic.mathdoc.fr/item/MAN_1983__263_163749/}
}