Membrane Computing 9th International Workshop, WMC 2008, Edinburgh, UK, July 28-31, 2008, Revised Selected and Invited Papers - Corne, David Wolfe; Frisco, Pierluigi; Păun, Gheorghe; Rozenberg, Grzegorz; Salomaa, Arto (Springer Berlin Heidelberg : Imprint: Springer, 2009)