@article{MM2_1975__15_154328,
     author = {Michael Wiegner},
     title = {\"Uber die {Regularit\"at} schwacher {L\"osungen} gewisser elliptischer {Systeme.}},
     journal = {Manuscripta mathematica},
     pages = {365--384},
     publisher = {mathdoc},
     volume = {15},
     year = {1975},
     zbl = {0312.35035},
     url = {http://geodesic.mathdoc.fr/item/MM2_1975__15_154328/}
}