Jesper Jansson Ngo Trung Hieu Wing-Kin Sung Local Gapped Subforest Alignment and Its Application in Finding RNA Structural Motifs. 569-580 http://springerlink.metapress.com/openurl.asp?genre=article&issn=0302-9743&volume=3341&spage=569 2004 conf/isaac/2004 ISAAC db/conf/isaac/isaac2004.html#JanssonHS04