@techreport {TR-1990-027,
   type = {Technical Report},
   author = {Christopher Barbour, Gary Meyer},
   title = {Visual Cues and Pictorial Limitations in Photorealistic Images },
   institution = {University of Oregon, Computer and Information Sciences Department},
   number = TR-1990-027,
   year = 1991,
   note = {Available at \url{https://www.cs.uoregon.edu/Reports/TR-1990-027.pdf}},
}