After World War I , Jean Cocteau and Les Six began to frequent a bar known as `` La gaya '' which became Le Bœuf sur le Toit ( The Ox on the Roof ) when the establishment moved to larger quarters .
They still remained friends , and used to visit a bar known as `` La Gaya '' which became Le Boeuf sur le Toit ( The Ox on the Roof ) : the title of Milhaud 's ballet .