I'm not certain which test Catmull used, but the article links to this one: https://wh.snapsurveys.com/s.asp?k=148940557153 https://wh.snapsurveys.com/s.asp?k=

I'm not certain which test Catmull used, but the article links to this one: https://wh.snapsurveys.com/s.asp?k=148940557153 https://wh.snapsurveys.com/s.asp?k=148940557153