A big thank-you to Steven Malinowski for producing the graphical score you see below.

The Trio No. 1 in B-flat major for piano, violin, and cello, D. 898, was written by Franz Schubert in 1827. The composer finished the work in 1828, in the last year of his life.[1][2] It was published in 1836 as Opus 99, eight years after the composer’s death.