WIA GC/10373 | Warburg, Aby to Guba, Anton 12/07/1906 | informs him that Warburg managed to raise M 300 so that his son can have painting lessons during... |
WIA GC/10443 | Warburg, Aby to Guba, Anton 29/09/1906 | his son had not paid Mr. [Walter] Voltmer, the painting teacher, although he maintained he had... |
WIA GC/10447 | Warburg, Aby to Guba, Anton 09/10/1906 | on his son's behaviour; Rudolf Guba did not pay the teacher, but turned to Warburg to borrow... |