@article{700081,
     title = {Regularity of potentials and removability of singularities of solutions of partial differential equations},
     booktitle = {Proceedings of Equadiff III},
     series = {GDML\_Books},
     publisher = {Univ. J. E. Purkyn\v e - P\v r\'\i rodov\v edeck\'a fakulta},
     address = {Brno},
     year = {1973},
     pages = {179-185},
     mrnumber = {MR0358053},
     zbl = {0318.35010},
     url = {http://dml.mathdoc.fr/item/700081}
}

Král, Josef. Regularity of potentials and removability of singularities of solutions of partial differential equations, dans Proceedings of Equadiff III, GDML_Books,  (1973), pp. 179-185. http://gdmltest.u-ga.fr/item/700081/