Basis functions for early vision
@TechReport{michaelisTR94a,
  author = 	 "M. Michaelis and G. Sommer
",
  title = 	 "Basis functions for early vision",
  institution =  "Inst. f. Inf. u. Prakt. Math.",
  year = 	 1994,
  number =       "9413",
  month =        "September",
  }