@misc{Campbell_John_Edward_(1862–1924)_Note_1891-1892,
 author={Campbell, John Edward (1862–1924)},
 volume={XXI},
 editor={Glaisher, James Whitbread Lee (1848–1928)},
 copyright={Public Domain},
 journal={The Messenger of Mathematics},
 address={London ;},
 address={Cambridge},
 howpublished={online},
 year={1891-1892},
 publisher={Macmillan and Co.},
 language={eng},
 language={eng},
 title={Note on the maximum number of arbitrary points which can be double points on a curve, or surface, of any degree},
 type={Text},
 URL={http://rcin.org.pl/impan/Content/109057/PDF/WA35_87712_cz294-1892-t21_Art27.pdf},
}