G. Borgefors.
  <b>Hierarchical chamfer matching: A parametric edge matching
  algorithm </b>.
  <i>IEEE Transactions on Pattern Analysis and Machine
  Intelligience</i>, 10:849-865, 1988.
  published
  <A HREF="http://vis.cs.brown.edu/results/bibtex/Borgefors-1988-HCM.bib">(bibtex:
  Borgefors-1988-HCM)</A>.<br />