In answer to the the question posed on the linked page 'who's the author?', probably Anthony Edwards (https://en.wikipedia.org/wiki/A._W._F._Edwards https://en.

In answer to the the question posed on the linked page 'who's the author?', probably Anthony Edwards (https://en.wikipedia.org/wiki/A._W._F._Edwards https://en.wikipedia.org/wiki/A._W._F._Edwards) see https://quentinsf.com/software/venn/ https://quentinsf.com/software/venn/ and https://www.cambridge.org/core/journals/combinatorics-probability-and-computing/article/sevenset-venn-diagrams-with-rotational-and-polar-symmetry/1DDA65063F444CD773CA3857C736C368 https://www.cambridge.org/core/journals/combinatorics-probab... and https://books.google.co.uk/books/about/Cogwheels_of_the_Mind.html?id=7_0Thy4V3JIC https://books.google.co.uk/books/about/Cogwheels_of_the_Mind...