There's also 'Group Explorer' by Nathan Carter. https://nathancarter.github.io/group-explorer/index.html https://nathancarter.github.io/group-explorer/index.ht

There's also 'Group Explorer' by Nathan Carter. https://nathancarter.github.io/group-explorer/index.html https://nathancarter.github.io/group-explorer/index.html The book is also very nice. edit: Oh right, that's linked from this page ...