OJ 5/7a, [10] (formerly vC 10) Handwritten letter from Schenker to Cube, dated June 1, 1927

Schenker congratulates Cube on appointment to professorship; reports that Oppel has been appointed to a professorship at the Leipzig Conservatory, and on the spread of Schenker's theory elsewhere; looks forward to visit from Cube.

OJ 6/7, [35] Handwritten letter from Schenker to Violin, dated August 5, 1927

In a wide-ranging letter, Schenker underscores the importance of his friend's taking a holiday, and tries to persuade him to visit him in Galtür. There he was visited by Reinhard Oppel, who has been appointed to a theory post at the Leipzig Conservatory, where he will teach from Schenker's texts. He comments at length on the decline of society, as exemplified by the July Revolt. The second Meisterwerk volume has gone to the bookbinders; until it is published, he will be working on Der freier Satz.

OJ 5/7a, [23] (formerly vC 23) Handwritten letter from Schenker to Cube, dated May 15, 1929

Gerhard Albersheim will leave a space in Schenker's calendar that Schenker offers to Erich Voss; will teach him himself because Weisse may not be up to date with Der freie Satz; Voss to contact him.

OJ 89/3, [6] Handwritten letter from Schenker to Hoboken, dated August 2, 1929

Schenker has passed the [fee] verdict on to Vrieslander; alludes to Reinhard Oppel, and advises on the analysis of Brahms Op. 117, No. 1.

OJ 89/6, [9] Handwritten letter from Schenker to Hoboken, dated July 25, 1933

In writing of Hoboken's prospects as a composer, Schenker is not interested in creating imitation Bachs and Brahmses. — He delights in Cortot's visit to the Photogram Archive - but Cortot belongs to the already convinced. — He makes observations on some inclosed feuilletons, and gives information about Goos.

Diary entry by Schenker for 16 December 1930

Diary entry by Schenker for 17 August 1931

Diary entry by Schenker for 9 November 1934