Edoardo Amaldi Claudio Iuliano Tomasz Jurkiewicz Kurt Mehlhorn Romeo Rizzi Breaking the O(m<sup>2</sup>n) Barrier for Minimum Cycle Bases. 301-312 2009 ESA http://dx.doi.org/10.1007/978-3-642-04128-0_28 conf/esa/2009 db/conf/esa/esa2009.html#AmaldiIJMR09