Psychology of slices

Years ago I remember a study that concluded people feel equally full after x number of slices of pizza, no matter what size, within reason. I remember the thought that cutting a buffet pizza into 12 would result in fewer pizzas used while people still eat all they want, and feel full.

Basically, size doesn’t matter. People will feel the same degree of full after eating 4 slices of a 12" pizza, whether it’s cut into 12 or 8.

Does anyone else remember this study? Has anything been done more recently than c. 1992?