WIA GC/2754
Sachs, Curt to Warburg, Aby 21/02/1907
forwards a copy of [Fritz] Knapp's 'Perugino' and requests a review
WIA GC/30058
Hornbostel, Erich Moritz von to Warburg, Aby 24/03/1925
thanks him for a letter and an article by Cassirer and Warburg's article [on Palazzo Schifanoia...