During his research, Christopher Hogwood came across an unpublished source which had not been taken into consideration for any previous edition.
While on a concert-tour in 1853 with the violinist Ede Reményi, the young Brahms visited Arnold Wehner, the Music Director of the Göttingen University. in Wehners Album Amicorum, which included contributions from Robert and Clara Schumann, Mendelssohn, Jenny Lind, Rossini and Liszt, Brahms had notated a short piano piece. The source consists of a one-page autograph of this literal Albumblatt (untitled by Brahms). The composer used it 12 years later, revised and transposed from A minor to A-flat minor in his Horn Trio.