Maximal regularity in interpolation spaces for second order Cauchy   problems
  We study maximal regularity in interpolation spaces for the sum of three closed linear operators on a Banach space, and we apply the abstract results to obtain Besov and H\"older maximal regularity for complete second order Cauchy problems under natural parabolicity assumptions. We discuss applications to partial differential equations. 
Charles J. K. Batty, Ralph Chill, Sachi Srivastava
math.FA math.AP math.DS