@article{10_21136_MB_2001_133926,
     author = {Chrastina, Jan},
     title = {Examples from the calculus of variations. {III.~Legendre} and {Jacobi} conditions},
     journal = {Mathematica Bohemica},
     pages = {93--111},
     publisher = {mathdoc},
     volume = {126},
     number = {1},
     year = {2001},
     doi = {10.21136/MB.2001.133926},
     mrnumber = {1826474},
     zbl = {0980.49024},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.21136/MB.2001.133926/}
}