@misc{Cayley_Arthur_(1821–1895)_Extract_1895,
 author={Cayley, Arthur (1821–1895)},
 copyright={Public Domain},
 address={Cambridge},
 journal={Mathematical papers},
 howpublished={online},
 year={1895},
 publisher={Cambridge University Press},
 language={eng},
 title={Extract from a letter from Prof. Cayley to Mr. C. W. Merrifield},
 type={Text},
 URL={http://www.rcin.org.pl/Content/135365/PDF/WA35_168119_12807-8_Art53.pdf},
}