The title page of Gottlob Frege's Begriffsschrift, original 1879 edition
2007-08-24
digitized version at <a rel="nofollow" class="external free" href="http://gallica.bnf.fr/ark:/12148/bpt6k65658c">http://gallica.bnf.fr/ark:/12148/bpt6k65658c</a>