Can we draw the following hypothesis from the context?

Context:

Morley College Choir was founded by Gustav Holst, during the period he was teaching music at Morley College. The choir was led for many years by Michael Tippett, who conducted the ensemble for the first-ever recording of Thomas Tallis' Spem in Alium, and premiered a number of Tippett's works, including A Child of Our Time in March 1944.

Hypothesis: Thomas Tallis was the composer of Spem in Alium
Yes