Markus Müller-Olm Helmut Seidl Analysis of Modular Arithmetic. 46-60 http://springerlink.metapress.com/openurl.asp?genre=article&issn=0302-9743&volume=3444&spage=46 2005 conf/esop/2005 ESOP db/conf/esop/esop2005.html#Muller-OlmS05