Michael Sammeth Gabriel Valiente Roderic Guigó Bubbles: Alternative Splicing Events of Arbitrary Dimension in Splicing Graphs. 372-395 2008 RECOMB http://dx.doi.org/10.1007/978-3-540-78839-3_32 conf/recomb/2008 db/conf/recomb/recomb2008.html#SammethVG08