An obituary on Wednesday about the harpsichordist, organist and conductor Gustav Leonhardt misspelled several names. One of the musicians who, like Mr. Leonhardt, made influential recordings on period instruments in the 1950s and 1960s was August Wenzinger, not Wenziger. The man with whom he studied organ and harpsichord at the Schola Cantorum in Basel, Switzerland, was Eduard Muller, not Miiller. And one of the churches in Amsterdam where Mr. Leonhardt has been organist is Waalse Kerk, not Waasle Kerk.