“…Since trees are an important class of graphs and since tree-like graphs arise in numerous applications, the idea of hyperbolicity has received attention in a range of applications. For example, it has found usefulness in the visualization of the Internet, the Web, and other large graphs [22,26,31]; it has been applied to questions of compact routing, navigation, and decentralized search in Internet graphs and small-world social networks [11,19,1,20,8]; and it has been applied to a range of other problems such as distance estimation, sensor networks, and traffic flow and congestion minimization [2,13,27,10].…”