@misc{Gallop_Edward_Gurner_(1862–1936)_On_1893-1894,
 author={Gallop, Edward Gurner (1862–1936)},
 volume={XXIII},
 editor={Glaisher, James Whitbread Lee (1848–1928)},
 copyright={Public Domain},
 journal={The Messenger of Mathematics},
 address={London ;},
 address={Cambridge},
 howpublished={online},
 year={1893-1894},
 publisher={Macmillan and Co.},
 language={eng},
 language={eng},
 title={On the cardinal points of an optical instrument},
 type={Text},
 URL={http://www.rcin.org.pl/impan/Content/110476/PDF/WA35_88030_cz294-1894-t23_Art23.pdf},
}