In 1923, Arturo Toscanini invited him to conduct Salome by Richard Strauss as the season opener at La Scala in Milan.

At the festival he conducted unusual operas such as Verdi's Luisa Miller, Spontini's La vestale, Cherubini's Médée and Gluck's Armide.

Notable writings include his 1924 study of Boito's opera Nerone, an article on "Mozart in Italy" from 1955, and his collected essays, Battute d'aspetto (1946).

His 1952 performance of Bellini's Norma with Callas on EMI is particularly prized, as is his pioneering 1937 complete recording of the opera with Gina Cigna in the title role and Ebe Stignani as Adalgisa, made in Turin.

In 1954 he conducted Spontini's Agnes von Hohenstaufen at the Maggio Musicale Fiorentino with Franco Corelli, Lucilla Udovich and Giangiacomo Guelfi.