Perfect numbers and finite groups
Rendiconti del Seminario Matematico della Università di Padova, Tome 129 (2013), pp. 17-34. 
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     volume = {129},
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     zbl = {1280.20026},
     language = {en},
     url = {http://archive.numdam.org/item/RSMUP_2013__129__17_0/}
}
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De Medts, Tom; Maróti, Attila. Perfect numbers and finite groups. Rendiconti del Seminario Matematico della Università di Padova, Tome 129 (2013), pp. 17-34. http://archive.numdam.org/item/RSMUP_2013__129__17_0/

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