 The band would include guest musicians such as Miguel O'Farrill and Elio Valdés, and they backed singer Merceditas Valdés, Barreto's wife since the late 1950s.Friends with another younger Cuban drummer, Hilario Durán, (Hilario worked with Guillermo in the Orquesta Cubana de Música Moderna) in 1991, he introduced Hilario to the Canadian flautist Jane Bunnett.Both men then went on to appear on her famous Afro-Cuban recording "Spirits of Havana".