One must be truly enamored of the internet that it allows one to find and read a copy of Bernhard Riemann’s doctoral thesis at the University of Göttingen from 1854!
Riemann,_Bernhard-On_the_Hypotheses_which_lie_at_the_Bases_of_Geometry_(1868).pdf (73 KB)
View this on posterous
His lovely and brief paper has created a tsunami of mathematical work and research in the ensuing 156 years. It has ultimately become one of the seminal works in the development of the algebra and calculus of n-dimensional manifolds.