no. 2
A free boundary problem with a volume penalization
Annali della Scuola Normale Superiore di Pisa - Classe di Scienze, Série 4, Tome 23 (1996) no. 2, pp. 249-300. 
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     author = {Lederman, C.},
     title = {A free boundary problem with a volume penalization},
     journal = {Annali della Scuola Normale Superiore di Pisa - Classe di Scienze},
     pages = {249--300},
     publisher = {Scuola normale superiore},
     volume = {Ser. 4, 23},
     number = {2},
     year = {1996},
     mrnumber = {1433424},
     zbl = {0889.49029},
     language = {en},
     url = {http://www.numdam.org/item/ASNSP_1996_4_23_2_249_0/}
}
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Lederman, C. A free boundary problem with a volume penalization. Annali della Scuola Normale Superiore di Pisa - Classe di Scienze, Série 4, Tome 23 (1996) no. 2, pp. 249-300. http://www.numdam.org/item/ASNSP_1996_4_23_2_249_0/

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