@book{403684, title = {Stavba Loba\v cevsk\'eho planimetrie}, series = {GDML\_Books}, publisher = {Mlad\'a fronta}, address = {Praha}, year = {1969}, language = {cs}, url = {http://dml.mathdoc.fr/item/403684} }
Gatial, Ján; Hejný, Milan. Stavba Lobačevského planimetrie. GDML_Books (1969), http://gdmltest.u-ga.fr/item/403684/