Artists researched for figure ground

I looked at a hand full of artist before designing my figure ground project. MC Escher I was already familiar with, but I still took another look at his work. He is very well known for his pieces where he starts with one animal and then takes the negative space and turns it into another animal all with the positive and negative space.
The next artist I looked at was Noma Bar. I was not familiar with her work before this project. She works with negative and positive space in a much more simplistic and cleaner way than MC Escher. I noticed she does a lot with faces. One of her pieces is a gun with the negative space in the trigger a face who's mouth is bleeding. I think all of her works are very creative.
Another artist I researched was Kara Walker. She does mostly silhouettes of people. Each piece is telling a story in a different way. The negative shapes she can make from these silhouettes are very strong and interesting.