@MISC{DT180,
   author = {Ekengren, Jens and Sj\"{o}holm, Johan and
             \"{O}stling, Daniel and Ros\'{e}n, Arne and
             Tomanek, David},
   title = {A comparison of the electronic structure and optical
            plasmons in Cs$_x$, Cs$_x$ shells and
            C$_{60}$Cs$_x$ clusters},
   howpublished = {unpublished},
   month = { },
   year = { },
   note = { } }