  Many real-world networks have properties of small-world networks, with
clustered local neighborhoods and low average-shortest path (ASP). They may
also show a scale-free degree distribution, which can be generated by growth
and preferential attachment to highly connected nodes, or hubs. However, many
real-world networks consist of multiple, inter-connected clusters not normally
seen in systems grown by preferential attachment, and there also exist
real-world networks with a scale-free degree distribution that do not contain
highly connected hubs. We describe spatial growth mechanisms, not using
preferential attachment, that address both aspects.
