Naoto Miyoshi Takeya Shigezumi Ryuhei Uehara Osamu Watanabe Scale Free Interval Graphs. 292-303 2008 AAIM http://dx.doi.org/10.1007/978-3-540-68880-8_28 conf/aaim/2008 db/conf/aaim/aaim2008.html#MiyoshiSUW08