A mixed problem for a Boussinesq hyperbolic equation with integral   condition
  A hyperbolic problem wich combines a classical(Dirichlet) and a non-local contraint is considered.The existence and uniqueness of strong solutions are proved,we use a functionnal analysis method based on a priori estimate and on the density of the range of the operator generated by the considered problem. 
Said Mesloub, Abdelouahab Mansour (ICJ)