Rosario Pugliese Francesco Tiezzi Nobuko Yoshida A Symbolic Semantics for a Calculus for Service-Oriented Computing. 135-164 2009 241 Electr. Notes Theor. Comput. Sci. http://dx.doi.org/10.1016/j.entcs.2009.06.008 db/journals/entcs/entcs241.html#PuglieseTY09