- 
OJ 10/3, [3] Typewritten postcard from Otto Erich Deutsch to Schenker, dated September 25, 1913
 Deutsch has forwarded Schenker's (non-extant) reply to Ludwig Scheibler, and states that Louis Koch
    has taken over the autograph manuscripts of Carl Meinert. 
- 
OC B/276 Typewritten letter from Louis Koch to Schenker, dated October 3, 1913
 Koch will send required information. 
- 
OC B/273 Typewritten letter from Louis Koch to Schenker, dated October 23, 1913
 Koch lists the Beethoven manuscript items in his possession. 
- 
OC B/274 Postal receipt for a letter from Schenker to Louis Koch, dated October 27,
    1913
 Postal receipt for letter of October 26, 1913 to Louis Koch. 
- 
OC B/272 Typewritten letter from Louis Koch to Schenker, dated October 28, 1913
 Koch agrees to supply photographs of Op. 110. 
- 
OC B/275 Handwritten letter from Louis Koch to Schenker, dated November 22, 1913
 Koch gives the provenance of the Op. 110 manuscript in his possession, and
        other information. 
- 
BNba 304g, [1] Handwritten letter from Schenker to F. A. Schmidt (Beethoven-Haus), dated November 27,
    1913
 Schenker asks the Beethoven-Haus to prepare and supply him with photographs of
    the autograph manuscript of the first movement of Beethoven's Piano Sonata in C minor, Op. 111,
    and announces the publication of his Erläuterungsausgabe of Op. 109 and monograph on Beethoven's
    Ninth Symphony. 
- 
OC B/269a-b Postal receipts for a letter and other item from Schenker to Louis Koch, dated November
    15, 1915
 Postal receipts for letter of November 14, 1915 and separate item to Louis
    Koch. 
- 
OC B/270 Typewritten letter from Louis Koch to Schenker, dated November 29, 1915
 Koch thanks Schenker for a copy of his elucidatory edition of Op. 111, and
        reports his Chopin holdings. 
- 
WSLB-Hds 95654 Handwritten letter from Schenker to Seligmann, dated July 24, 1916
 Schenker tells Seligmann that he has arranged for copies of his critical
        editions of Beethoven’s Op. 110 and Op. 111 to be sent to him. He speaks of the positive
        interest his works have received in Germany, and about Hugo Riemann asking him to provide
        autobiographical material for an entry in the next edition of his music
        lexicon. 
- 
OJ 10/1, [46] Handwritten postcard from Dahms to Schenker, dated October 17, 1919
 Dahms reports on the present whereabouts of the autograph manuscript of Beethoven
    Op. 101.  
- 
OC 52/209 Postal receipt for letter from Schenker to Louis Koch, dated November 3,
    1919
 Postal receipt for a registered letter from Schenker to Louis
    Koch. 
- 
OC B/268 Typewritten letter from Louis Koch to Schenker, dated December 10, 1919
 Koch asks about the format of the required photography. 
- 
WSLB 310 Handwritten letter from Schenker to Hertzka (UE), dated December 17, 1919
 Louis Koch has given consent; Schenker asks Hertzka to pick up the photographs
    while in Frankfurt; they need to discuss how Schenker allocates his time for the Kleine
    Bibliothek and other tasks.  
- 
OC 52/507-508 Typed letter from Hertzka (UE) to Schenker, dated December 19, 1919
 Hertzka is pleased that Louis Koch has given his consent [for Op. 101]; he
    suggests that UE obtain certain sources from the Gesellschaft der Musikfreunde Archive on loan
    at the office for Schenker to work on; and offers a larger fee for Op. 101, and cautions
    Schenker about growing costs of photographic work.  
- 
WSLB 305 Handwritten letter from Schenker to Hertzka (UE), dated December 21, 1919
 Schenker informs Hertzka that he has ordered two more Beethoven sketchbooks in
    connection with Op. 101, and asks him for some other "apportionment," which will protect him
    from long-term deterioration of the exchange rate.  
- 
OJ 10/3, [7] Handwritten letter from Otto Erich Deutsch Deutsch to Schenker, dated January 16,
        1920
 Deutsch will write to the Beethoven House in Bonn to seek permission to
        reproduce the manuscript of the "Moonlight" Sonata. He suggests using the first edition as
        the source for the missing opening and closing bars, and asks Schenker to refrain from
        polemics in his commentary. Copies of the manuscripts of Beethoven's piano sonatas Opp. 28,
        109, 110 and 111 should not be difficult to obtain, and he has made inquiries regarding the
        manuscripts of Beethoven's Piano Sonata Op. 106 and Mozart's A minor Rondo K.
        511. 
- 
OC B/267 Typewritten letter from Louis Koch to Schenker, dated February 27, 1920
 Koch is sending photographs separately. 
- 
OC B/261 Handwritten invoice from Gustav Rapp & Co. to Schenker, dated March 8,
        1920
 Invoice for photographic copies [of Beethoven, Op. 101]. 
- 
OC B/260 Handwritten letter from Gustav Rapp & Co. to Schenker, dated March 9,
        1920
 Rapp encloses invoice. 
- 
OC B/266 Typewritten postcard from Louis Koch to Schenker, dated March 9, 1920
 Koch hopes photographs have arrived. 
- 
OC 52/220 Typed letter from Hertzka (UE) to Schenker, dated March 13, 1920
 Hertzka thanks Schenker for commiserations, expresses pleasure that the
    photographs [of Op. 101] have arrived, and seeks a meeting to discuss the Kleine Bibliothek.  
- 
OJ 10/3, [37] Typewritten postcard from Deutsch to Schenker, dated May 26, 1922
 Deutsch reports that Drei Masken will not publish a facsimile edition of Beethoven's "Spring"
        Sonata Op. 24, and will instead publish editions of Beethoven's Piano Sonata in F-sharp Op. 78, a string quartet
        by Haydn, and Schubert's Winterreise and B minor Symphony. 
- 
OJ 89/1, [2] Handwritten letter from Schenker to van Hoboken, dated August 12, 1927
 Schenker acknowledges van Hoboken's letter, OJ 11/54, 14, dated August 7, 1927;
    encloses seven articles; responds regarding Haydn, Furtwängler, the "Appeal" for the
    Photogrammarchiv, an exhibition in Frankfurt, John Petrie Dunn, Reinhard Oppel, Das Meisterwerk
    in der Musik, vol. II, Otto Erich Deutsch, and an honorarium; and sends best wishes for the
    Hobokens' trip to Switzerland, reporting on von Cube. 
- 
OJ 11/54, [15] Handwritten letter from van Hoboken to Schenker, dated August 28, 1927
 Hoboken reports on meeting with Furtwängler regarding the Photogrammarchiv, and
    expresses the hope that it will be possible to interest Furtwängler in performance according to
    the sources in the Archive; he encloses the final version of the "Aufruf" for the Archive, and
    discusses negotiations with the Austrian National Library and Ministry of Education. — Comments
    on Oppel's plan to teach in Leipzig. — Agrees to Schenker's lesson plan and fee for 1927/28. —
    Describes his travel plans, which include meetings with Louis Koch in Frankurt, Ludwig
    Schiedermair in Bonn, contact with John Petrie Dunn in England, C. S. Terry in Scotland, and
    Maurice Cauchie in Paris, and photographing [of sources] at the [Paris] Conservatory.  
- 
OJ 5/7a, [11] (formerly vC 11) Handwritten postcard from Schenker to Cube, dated September 7, 1927
 Schenker acknowledges Cube's postcards; Cube will receive the appeal [for photostats of
        MSS]. 
- 
OJ 10/3, [74] Typewritten postcard from Deutsch to Schenker, dated November 22, 1927
 Deutsch suspects that with the typesetters' "messing up" of Schenker’s revised
        copy of Schubert’s “Unfinished” Symphony the material has been made illegible. — He has been
        in contact with people regarding a possible radio talk by Schenker, and one by himself on
        the redesigning of the Mozarteum. — He reports that the pianist Heinz Jolles would like
        Schenker to prepare an edition of one of Beethoven’s variation sets (WoO 80 or the
        “Diabelli”), and that Josef Braunstein is gratified to hear of Schenker’s interest in his
        recent book on the "Leonore" overtures. 
- 
OJ 10/3, [114] Typewritten letter from Deutsch to Schenker, dated January 21, 1930
 Deutsch explains that, without a fixed annual budget, the Board of Trustees
        [of the Photogram Archive] is unable to function properly. Hoboken didn’t always deal
        efficiently with the foreign contributors to the collection; a catalogue has still not been
        prepared. And Deutsch has made himself ill by overwork. Hedwig Kraus has taken over the
        directorship of the Archive of the Gesellschaft der Musikfreunde, with [Karl] Geiringer as
        her assistant – to whom Deutsch would have greatly preferred Luithlen. He has been
        exchanging letters with Vrieslander. 
- 
OJ 11/32, [13] Typed letter from Robert Haas to Schenker, dated December 22, 1932
 Haas gives information about an early copy of a Beethoven
        score.