Henrik Pilegaard Flemming Nielson Hanne Riis Nielson Active Evaluation Contexts for Reaction Semantics. 57-70 2007 175 Electr. Notes Theor. Comput. Sci. 1 http://dx.doi.org/10.1016/j.entcs.2006.09.014 db/journals/entcs/entcs175.html#PilegaardNN07