@misc{Sylvester_James_Joseph_(1814–1897)_Sur_1912,
 author={Sylvester, James Joseph (1814–1897)},
 copyright={Public Domain},
 address={Cambridge},
 howpublished={online},
 year={1912},
 publisher={Cambridge University Press},
 language={eng},
 type={Text},
 title={Sur les nombres parfaits},
 URL={http://www.rcin.org.pl/Content/122675/PDF/WA35_145315_11371-4_Art58.pdf},
}