Original: Those making their Prom debuts in the Sargent years included Carlo Maria Giulini, Georg Solti, Leopold Stokowski, Rudolf Kempe, Pierre Boulez and Bernard Haitink.
Simplified: During his time at the Proms foreign conductors such as Carlo Maria Giulini, Georg Solti, Leopold Stokowski, Rudolf Kempe, Pierre Boulez and Bernard Haitink were invited to perform.