Avneesh Sud Mark Foskey Dinesh Manocha Homotopy-Preserving Medial Axis Simplification. 423-451 2007 17 Int. J. Comput. Geometry Appl. 5 http://dx.doi.org/10.1142/S0218195907002434 db/journals/ijcga/ijcga17.html#SudFM07