- The Oster collection [microform] : papers of Heinrich Schenker /
- File 34: Analyses of Music by Brahms /
- Label by Ernst Oster: "Brahms, Intermezzi Op. 117 / "Philologisch" /
- Recto: Sketches for a graph of Variationen über ein eigenes Thema, Op. 21, No. 1, D Major, Theme