Leonard Kleinrock Willard Korfhage Collecting Unused Processing Capacity: An Analysis of Transient Distributed Systems. 535-546 1993 4 IEEE Trans. Parallel Distrib. Syst. 5 http://doi.ieeecomputersociety.org/10.1109/71.224216 db/journals/tpds/tpds4.html#KleinrockK93