@article{10_4064_cm97_1_7,
     author = {Piotr Gwiazda},
     title = {An existence result for balance laws
 with multifunctions: a model from the theory
 of granular media},
     journal = {Colloquium Mathematicum},
     pages = {67--79},
     publisher = {mathdoc},
     volume = {97},
     number = {1},
     year = {2003},
     doi = {10.4064/cm97-1-7},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.4064/cm97-1-7/}
}