- Year 1908. 22-05-1908 Letter to Alma Mahler (1879-1964).
- Year 1908. 08-09-1908 Letter to Alma Mahler (1879-1964).
- Year 1908. 10-09-1908 Letter to Alma Mahler (1879-1964).
- Year 1908. 11-09-1908 Letter to Alma Mahler (1879-1964).
See: Pictures and more on 1885 Hotel Blauen Stern (23 year before).