Colm Mulcahy - Martin Gardner's Little-Known Collaborations - G4G12 April 2016

Picked one by one from a mixed channel; title passed two strict editor passes and the clickbait rules.

A 7-minute video from G4G Celebration: “Colm Mulcahy - Martin Gardner's Little-Known Collaborations - G4G12 April 2016”.

Video by G4G Celebration, played through YouTube's embedded player.