@techreport {TR-1994-001,
   type = {Technical Report},
   author = {Jay S. Gondek, Gary W. Meyer, Jonathan G. Newman },
   title = {Wavelength Dependent Reflectance Functions },
   institution = {University of Oregon, Computer and Information Sciences Department},
   number = TR-1994-001,
   month = 1,
   year = 1994,
   note = {Available at \url{https://www.cs.uoregon.edu/Reports/TR-1994-001.pdf}},
}