no. 2
The ⊕ c -topology on abelian p-groups
Annali della Scuola Normale Superiore di Pisa - Classe di Scienze, Série 4, Tome 7 (1980) no. 2, pp. 241-256. 
@article{ASNSP_1980_4_7_2_241_0,
     author = {D'Este, Gabriella},
     title = {The $\oplus \_c$-topology on abelian $p$-groups},
     journal = {Annali della Scuola Normale Superiore di Pisa - Classe di Scienze},
     pages = {241--256},
     publisher = {Scuola normale superiore},
     volume = {Ser. 4, 7},
     number = {2},
     year = {1980},
     zbl = {0439.20034},
     language = {en},
     url = {archive.numdam.org/item/ASNSP_1980_4_7_2_241_0/}
}
D'Este, G. The $\oplus _c$-topology on abelian $p$-groups. Annali della Scuola Normale Superiore di Pisa - Classe di Scienze, Série 4, Tome 7 (1980) no. 2, pp. 241-256. http://archive.numdam.org/item/ASNSP_1980_4_7_2_241_0/

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