Other Capability Operating Systems

or systems from which Keykos took ideas. Subsequent systems or systems we should have known about but didn’t. A Hydra book: William Allan Wulf, Hydra C.mmp: An Experimental Computer System, McGraw Hill,
June 1981 ISBN: 0070721203
Hydra clue.

The following book describes several capability based systems and their software.

Henry M. Levy, Capability Based Computer Systems, Digital Press, 1984.

Juicy History of Windows