Patrick Baillot Virgile Mogbil Soft lambda-Calculus: A Language for Polynomial Time Computation. 27-41 http://springerlink.metapress.com/openurl.asp?genre=article&issn=0302-9743&volume=2987&spage=27 2004 conf/fossacs/2004 FoSSaCS db/conf/fossacs/fossacs2004.html#BaillotM04