no. 2
A class of pseudo differential operators on the product of two manifolds and applications
Annali della Scuola Normale Superiore di Pisa - Classe di Scienze, Série 4, Tome 2 (1975) no. 2, pp. 287-302. 
@article{ASNSP_1975_4_2_2_287_0,
     author = {Rodino, Luigi},
     title = {A class of pseudo differential operators on the product of two manifolds and applications},
     journal = {Annali della Scuola Normale Superiore di Pisa - Classe di Scienze},
     pages = {287--302},
     publisher = {Scuola normale superiore},
     volume = {Ser. 4, 2},
     number = {2},
     year = {1975},
     zbl = {0308.35081},
     mrnumber = {397800},
     language = {en},
     url = {archive.numdam.org/item/ASNSP_1975_4_2_2_287_0/}
}
Rodino, Luigi. A class of pseudo differential operators on the product of two manifolds and applications. Annali della Scuola Normale Superiore di Pisa - Classe di Scienze, Série 4, Tome 2 (1975) no. 2, pp. 287-302. http://archive.numdam.org/item/ASNSP_1975_4_2_2_287_0/

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