“Farkas Bolyai, as quoted by Florian Cajori, A History of Mathematics (1894) p. 302 books.google, citing Franz Schmidt, "Aus dem Leben zweier ungarischer Mathematiker Johann und Wolfgang Bolyai von Bolya," Grunert's Archiv, 48:2, 1868, p. 226 books.google”

Source: Wikiquote