On Fast Diffusion Nonlinear Heat Equations and a Related Singular Elliptic Problem Panagiota DaskalopoulosManuel del Pino Indiana University Mathematics Journal 1994 text pdf 10.1512/iumj.1994.43.43030 10.1512/iumj.1994.43.43030 en Indiana Univ. Math. J. 43 (1994) 703 - 728 state-of-the-art mathematics http://iumj.org/access/