Amanda M. Holland-Minkley Regina Barzilay Robert L. Constable Verbalization of High-Level Formal Proofs. 277-284 1999 conf/aaai/1999 AAAI/IAAI db/conf/aaai/aaai99.html#Holland-MinkleyBC99 http://www.aaai.org/Library/AAAI/1999/aaai99-041.php