@misc{Cayley_Arthur_(1821–1895)_On_1889, author={Cayley Arthur (1821–1895)}, copyright={Public Domain}, address={Cambridge}, journal={Mathematical papers}, howpublished={online}, year={1889}, publisher={Cambridge University Press}, language={eng}, type={Text}, title={On the Singularities of Surfaces}, URL={http://rcin.org.pl/Content/122042/PDF/WA35_149081_12807-2_Art6.pdf}, }