G. William Skinner, "Marketing and Social Structure in Rural China," provenance unknown (images taken from a badly-constructed bootleg book found in a thrift store some years ago)

FOUR SPATIAL MODELS OF CENTRAL MARKETING SYSTEMS

At the center of each model is, of course, a central market town. Open dots represent standard market towns, while the heavier dots around the rim of each system represent intermediate market towns. Villages are not shown. When markets at all levels are distributed consistently according to Model A or Model B, the result is systems as shown in AA or BB, respectively.