@article{ASNSP_1963_3_17_1-2_1_0,
     author = {Peetre, Jaak},
     title = {Mixed problems for higher order elliptic equations in two variables, {II}},
     journal = {Annali della Scuola Normale Superiore di Pisa - Classe di Scienze},
     pages = {1--12},
     publisher = {Scuola normale superiore},
     volume = {Ser. 3, 17},
     number = {1-2},
     year = {1963},
     mrnumber = {157088},
     zbl = {0115.31602},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/ASNSP_1963_3_17_1-2_1_0/}
}