A directed network of Greek and Roman mythology

We construct a directed network using a dictionary of Greek and Roman mythology in which the nodes represent the entries listed in the dictionary and we make directional links from an entry to other entries that appear in its explanatory part. We find that this network is clearly not a random network but a directed scale-free network in which the distributions of out-degree and in-degree follow a power-law with exponents gamma(out) approximate to 3.0 and gamma(in) approximate to 2.5, respectively. Also we measure several quantities which describe the topological properties of the network and compare it to that of other real networks. (C) 2007 Elsevier B.V. All rights reserved.