I was approached by a student a few months ago — he was writing his dissertation and needed examples to illustrate the seventeen symmetry groups: “My name is Carlos, I’m Brazilian. I am to defend my (master’s) thesis in mathematics, at the end of September, it deals with the 17 groups of symmetry in the plan. As your drawings show what these symmetries can do and how beautiful they are, I would use some in my work if possible. I’m sending them already edited the way I would use them.
Since it is an academic work, I need permission to use the images.”