The City Is a Tree; The Real World Is Not a Tree!

摘要

The guest coeditors of this issue set a context in which to view a previously unpublished article of Frank Harary. The Harary article is followed here by contemporary material of Joseph Kerski that addresses similar real-world issues. The two together, along with the context, serve as a springboard to launch the reader into the rest of the materials in this special issue devoted to graph theory and network science.