Tentamen juventutem studiosam in elementa matheseos purae, elementaris ac sublimioris, methodo intuitiva, evidentiaque huic propria, introducendi
116. Independently of both Lobachevskii and Gauss, Janos Bolyai produced his own system of non-Euclidean geometry which was published as an appendix to his father Farkas's larger work. This privately printed work was poorly printed by a an obscure college publisher in a run of about 150 copies in a small city in Hungary (now known as Targu Mures in Rumania) and few people noticed it at the time.Nevertheless, it is regarded as a remarkable mathematical achievement and upon its rediscovery in the early 1900s it was crucial for the mathematical basis of relativity theory. This work is very rare and less than twenty copies of the complete work are known to exist in the world. The actual Herald of Science 116 is the 28-page appendix to volume 1 (following p. 502), Scientiam spatii absolute veram exhibens.