no. 1
Some properties of the Y-method of summability in complete ultrametric fields
Annales Mathématiques Blaise Pascal, Tome 9 (2002) no. 1, pp. 79-84. 
@article{AMBP_2002__9_1_79_0,
     author = {Natarajan, P.N.},
     title = {Some properties of the $Y$-method of summability in complete ultrametric fields},
     journal = {Annales Math\'ematiques Blaise Pascal},
     pages = {79--84},
     publisher = {Laboratoires de Math\'ematiques Pures et Appliqu\'ees de l'Universit\'e Blaise Pascal},
     volume = {9},
     number = {1},
     year = {2002},
     zbl = {01805822},
     mrnumber = {1914262},
     language = {en},
     url = {www.numdam.org/item/AMBP_2002__9_1_79_0/}
}
Natarajan, P.N. Some properties of the $Y$-method of summability in complete ultrametric fields. Annales Mathématiques Blaise Pascal, Tome 9 (2002) no. 1, pp. 79-84. http://www.numdam.org/item/AMBP_2002__9_1_79_0/

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