Ting Zhang Henny B. Sipma Zohar Manna Decision Procedures for Recursive Data Structures with Integer Constraints. 152-167 http://springerlink.metapress.com/openurl.asp?genre=article&issn=0302-9743&volume=3097&spage=152 2004 conf/cade/2004 IJCAR db/conf/cade/ijcar2004.html#ZhangSM04