An Braeken Christopher Wolf Bart Preneel A Study of the Security of Unbalanced Oil and Vinegar Signature Schemes. 29-43 http://springerlink.metapress.com/openurl.asp?genre=article&issn=0302-9743&volume=3376&spage=29 2005 conf/ctrsa/2005 CT-RSA db/conf/ctrsa/ctrsa2005.html#BraekenWP05