1. S. Alagić, Natural State Transformations, COINS Technical Report 73B-2, University of Massachusetts at Amherst, 1973.
2. M. A. Arbib and E. G. Manes, Machines in a Category, SIAM Review, April, 1974.
3. M. A. Arbib and E. G. Manes, The Monoid of a Machine in a Category, to appear.
4. M. A. Arbib and E. G. Manes, Adjoint Machines, State Behaviour Machines, and Duality, Technical Report '73B-1, February, 1973, Computer and Information Science, University of Massachusetts, Amherst; to appear in J. Pure Appl. Alg.
5. M. A. Arbib and E. G. Manes, Kleisli Machines, to appear.