Ryosuke Cohen is a mail artist from Ashiya-City, Hyogo, Japan. His now famous Brain Cell mail art is circulating all over the world. In this ongoing project, Ryosuke asks other mail artists to contribute their designs, rubber stamps, stickers or seals and he incorporate them in his A3 size sheets. Each sheet is numbered and has a list of artists included in that particular issue. More about the project you may find here and here.
This is the Brain Cell 1015.