A group of sketches is found in the  Theatermuseum (theatre collection) in Vienna, as part of the estate of the singer Anna Bahr-von Mildenburg (1872-1947). They are contained in a sketchbook that Mahler probably used at the very end of his life.

A card by Anna Bahr-von Mildenburg (1872-1947) accompanying the small volume bears the following inscription: “Gustav Mahler’s last sketchbook. It lay on his breast when he died. His father-in-law (the painter Carl Julius Rudolf Moll (1861-1945)) took it with him and gave it to me today, 25-01-1943 when he visited me. I also gave him letters from Gustav Mahler to read”.

Part of the sketches is the Last sketchbook Symphony No. 7.