Classical and nonclassical symmetries of a generalized Boussinesq   equation
  We apply the Lie-group formalism and the nonclassical method due to Bluman and Cole to deduce symmetries of the generalized Boussinesq equation, which has the classical Boussinesq equation as an special case. We study the class of functions $f(u)$ for which this equation admit either the classical or the nonclassical method. The reductions obtained are derived. Some new exact solutions can be derived. 
Maria Luz Gandarias, M. S. Bruz\'on