Robert J. Renka.
  <b>Multivariate Interpolation of LArge Sets of Scattered Data</b>.
  <i>ACM Transactions on Mathematical Software</i>, 14(2):139-148, June
  1988.
  <A HREF="http://vis.cs.brown.edu/docs/pdf/bib/g/Renka-1988-MIL.pdf.html">(pdf)</A>
  <A HREF="http://vis.cs.brown.edu/results/bibtex/Renka-1988-MIL.bib">(bibtex:
  Renka-1988-MIL)</A>.<br />