@misc{Cayley_Arthur_(1821–1895)_Sur_1889, author={Cayley Arthur (1821–1895)}, copyright={Public Domain}, address={Cambridge}, journal={Mathematical papers}, howpublished={online}, year={1889}, publisher={Cambridge University Press}, language={eng}, title={Sur le Problème des Contacts}, type={Text}, URL={http://www.rcin.org.pl/Content/119137/PDF/WA35_143577_12807-1_Art91.pdf}, }