Scheme 84 interim reference manual. Indiana University Computer Science Technical Report 153, January 1985. Christopher T. Haynes. Springer-Verlag, July 1986. Christopher T. Haynes and Daniel P. Friedman.
Engines build process abstractions.
Abstracting timed preemption with engines. Christopher T. Haynes and Daniel P. Friedman. Embedding continuations in procedural objects. Christopher T. Haynes and Daniel P. Friedman and Mitchell Wand. Obtaining coroutines with continuations.