Ashok Kumar Ponnuswami H. Venkateswaran Monotone Multilinear Boolean Circuits for Bipartite Perfect Matching Require Exponential Size. 460-468 http://springerlink.metapress.com/openurl.asp?genre=article&issn=0302-9743&volume=3328&spage=460 2004 conf/fsttcs/2004 FSTTCS db/conf/fsttcs/fsttcs2004.html#PonnuswamiV04