Stanisław Gołąb

Stanisław Gołąb (July 26, 1902 – April 30, 1980) was a Polish mathematician from Kraków, working in particular on the field of affine geometry.

In 1932, he proved that the perimeter of the unit disc respect to a given metric can take any value in between 6 and 8, and that these extremal values are obtained if and only if the unit disc is an affine regular hexagon resp. a parallelogram. Provided by Wikipedia