@incollection {MR2436108,
    AUTHOR = {Sarkis, Marcus and Schaerer, Christian E. and Mathew, Tarek},
     TITLE = {Block diagonal parareal preconditioner for parabolic optimal
              control problems},
 BOOKTITLE = {Domain decomposition methods in science and engineering
              {XVII}},
    SERIES = {Lect. Notes Comput. Sci. Eng.},
    VOLUME = {60},
     PAGES = {409--416},
 PUBLISHER = {Springer},
   ADDRESS = {Berlin},
      YEAR = {2008},
   MRCLASS = {49M25 (49N10 65M60)},
  MRNUMBER = {2436108},
       DOI = {10.1007/978-3-540-75199-1_52},
       URL = {http://dx.doi.org/10.1007/978-3-540-75199-1_52},
}