Critical points of solutions to the obstacle problem in the plane
Annali della Scuola Normale Superiore di Pisa - Classe di Scienze, Série 4, Volume 21 (1994) no. 2, p. 157-173
@article{ASNSP_1994_4_21_2_157_0,
     author = {Sakaguchi, Shigeru},
     title = {Critical points of solutions to the obstacle problem in the plane},
     journal = {Annali della Scuola Normale Superiore di Pisa - Classe di Scienze},
     publisher = {Scuola normale superiore},
     volume = {Ser. 4, 21},
     number = {2},
     year = {1994},
     pages = {157-173},
     zbl = {0823.35068},
     mrnumber = {1288362},
     language = {en},
     url = {http://www.numdam.org/item/ASNSP_1994_4_21_2_157_0}
}
Sakaguchi, Shigeru. Critical points of solutions to the obstacle problem in the plane. Annali della Scuola Normale Superiore di Pisa - Classe di Scienze, Série 4, Volume 21 (1994) no. 2, pp. 157-173. http://www.numdam.org/item/ASNSP_1994_4_21_2_157_0/

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