Some special properties of solutions to obstacle problems
Rendiconti del Seminario Matematico della Università di Padova, Volume 71 (1984), p. 121-129 
@article{RSMUP_1984__71__121_0,
     author = {Maderna, Carla and Salsa, Sandro},
     title = {Some special properties of solutions to obstacle problems},
     journal = {Rendiconti del Seminario Matematico della Universit\`a di Padova},
     publisher = {Seminario Matematico of the University of Padua},
     volume = {71},
     year = {1984},
     pages = {121-129},
     zbl = {0562.35014},
     mrnumber = {769431},
     language = {en},
     url = {http://www.numdam.org/item/RSMUP_1984__71__121_0}
}

Maderna, Carla; Salsa, Sandro. Some special properties of solutions to obstacle problems. Rendiconti del Seminario Matematico della Università di Padova, Volume 71 (1984) pp. 121-129. http://www.numdam.org/item/RSMUP_1984__71__121_0/

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