Negri v. Stop and Shop, Inc., 65 N.Y.2d 625, 480 N.E.2d 740 (1985) p 76.

A woman slipped and fell, injuring herself, on baby food that was on the floor of this grocery store. The baby food appeared to have been on the ground for sometime. The store was found negligent because they had plenty of time in which to discover and clean up the spilled baby food.

Gordon v. American Museum of Natural History, 67 N.Y.2d 836 (1986) p76

P slipped on a piece of waxy paper while descending some stairs. The paper came form a concession stand. P claimed that D was negligent by not discovering and removing the paper. Court found that the paper must exist for a long enough time in order for it to be discovered and removed. There is no evidence that anyone observed the paper. Therefore D was not negligent.