%0 Journal Article
%T La F¨®rmula Fundamental de la Geometr¨ªa no Euclidiana
%A Andr¨¦s Chaves Beltr¨¢n
%J Revista Sigma
%D 2009
%I 
%X One appears two different forms to obtain the formula of non-euclidian geometry. First assuming the idea of Taurinus, over the formulas hyperbolic geometry are obtained soon from the trigonometry of a sphere with imaginary radio and finally whit rigor of Lobachevsky in their book.
%K Non-euclideans geometry
%K hyperbolic geometry
%K spheric trigonometry
%K angle of parallelism
%U http://revistasigma.udenar.edu.co/articulos/articulosIX2/1.pdf