Hewitt, C. et al "Laws for Communicating Parallel Processes" pp987-992

Information Processing 77 (Proc. (1977) Information Processing 77 (Proc. IFIP Congress 77, Toronto, August 8-12, 1977), Vol. 7, Elsevier North-Holland, Inc., New York, 1977  

Languages mentioned Actors {1971} Agent based object parallel language