Balancing the EULISP Metaobject Protocol. - Harry Bretthauer; Jürgen Kopp; Harley Davis; Keith Playford (LISP Symb. Comput., 1993)

A Monotonic Superclass Linearization for Dylan. - Kim Barrett; Bob Cassels; Paul Haahr; David A. Moon; Keith Playford; P. Tucker Withington (OOPSLA, 1996)

The Java Syntactic Extender. - Jonathan Bachrach; Keith Playford (OOPSLA, 2001)