How long was the longest tennis match in Grand slams?

Mens singles - Roger Federer, 15 Slams

Mens combined singles and doubles and mixed doubles - Roy Emerson, 28 Slams (12 singles, 16 doubles, 0 mixed doubles)

Women's singles - Margaret Court Smith, 24 Slams

Women's combined singles and doubles - Margaret Court Smith, 62 Slams (24 singles, 19 doubles, 19 mixed doubles)