Randall has also been undertaking a PhD at the Royal College of Music under the heading “The changing voice of Francesco Bernardi (known as Senesino): Case studies in Italian opera, 1707-1737.” This has resulted in his performance of the works of the little known composer Giovanni Antonio Giaj. You can hear some of Gaij's music in the YouTube Videos section of Randall's Countertenor Corner Profile.
You can also hear one of the arias below.