@misc{Knox_Alexander_Differential_1884, author={Knox, Alexander}, copyright={Public Domain}, address={London}, howpublished={online}, year={1884}, publisher={Macmillan and Co.}, language={eng}, title={Differential calculus for beginners : with a selection of easy examples}, type={Text}, URL={http://rcin.org.pl/Content/73672/PDF/WA35_6895_4507_Differential_calculus.pdf}, }