no. 4
Some non-homogeneous symbols and associated pseudo-differential operators
Annali della Scuola Normale Superiore di Pisa - Classe di Scienze, Série 3, Tome 21 (1967) no. 4, pp. 547-574. 
@article{ASNSP_1967_3_21_4_547_0,
     author = {Zaidman, Samuel},
     title = {Some non-homogeneous symbols and associated pseudo-differential operators},
     journal = {Annali della Scuola Normale Superiore di Pisa - Classe di Scienze},
     pages = {547--574},
     publisher = {Scuola normale superiore},
     volume = {Ser. 3, 21},
     number = {4},
     year = {1967},
     zbl = {0155.43403},
     mrnumber = {224978},
     language = {en},
     url = {archive.numdam.org/item/ASNSP_1967_3_21_4_547_0/}
}
Zaidman, S. Some non-homogeneous symbols and associated pseudo-differential operators. Annali della Scuola Normale Superiore di Pisa - Classe di Scienze, Série 3, Tome 21 (1967) no. 4, pp. 547-574. http://archive.numdam.org/item/ASNSP_1967_3_21_4_547_0/

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