David Sankoff Jean-François Lefebvre Elisabeth R. M. Tillier Adrian Maler Nadia El-Mabrouk The Distribution of Inversion Lengths in Bacteria. 97-108 http://springerlink.metapress.com/openurl.asp?genre=article&issn=0302-9743&volume=3388&spage=97 2004 conf/recomb/2004rcg Comparative Genomics db/conf/recomb/rcg2004.html#SankoffLTME04