David B. Chandler Maw-Shang Chang Ton Kloks Van Bang Le Sheng-Lung Peng Probe Ptolemaic Graphs. 468-477 2008 COCOON http://dx.doi.org/10.1007/978-3-540-69733-6_46 conf/cocoon/2008 db/conf/cocoon/cocoon2008.html#ChandlerCKLP08