[Minsky81] N. Minsky, On the Transport of Privileges, 1981 IEEE Symposium on Security and Privacy, Oakland, CA pp41-48, 1981. [This paper introduces a mechanism for transporting or authorization privileges called Send-Recieve which allows the potential power of a subject to be analyzed.] See also, "Selective and Locally Controlled Transport of Privileges, ACM Trans on Programming Languages and Systems, V6(4), October, 1984 pp 573-602 for more detailed coverage.