Transformations of Self-Similar Solutions for porous medium equations of   fractional type
  We consider four different models of nonlinear diffusion equations involving fractional Laplacians and study the existence and properties of classes of self-similar solutions. Such solutions are an important tool in developing the general theory. We introduce a number of transformations that allow us to map complete classes of solutions of one equation into those of another one, thus providing us with a number of new solutions, as well as interesting connections. Special attention is paid to the property of finite propagation. 
Diana Stan, F\'elix del Teso, Juan Luis V\'azquez
math.AP