@article{ASNSP_1972_3_26_2_325_0,
     author = {Andreotti, Aldo and Denson Hill, C.},
     title = {E. {E.} {Levi} convexity and the {Hans} {Lewy} problem. {Part} {I} : reduction to vanishing theorems},
     journal = {Annali della Scuola Normale Superiore di Pisa - Scienze Fisiche e Matematiche},
     pages = {325--363},
     publisher = {Scuola normale superiore},
     volume = {Ser. 3, 26},
     number = {2},
     year = {1972},
     mrnumber = {460725},
     language = {en},
     url = {http://archive.numdam.org/item/ASNSP_1972_3_26_2_325_0/}
}