Magnetic Rag.
Composed around 1912-13 by Scott Joplin this might very well be the last ragtime he composed by himself and didn't co-write with anyone else. In particular, it has a long C section of 24 bars and the D section modulates directly to tonic minor.
Solo Score.
Pure Duo Sheet Music, Arrangement for Trumpet and Trombone by Lars Christian Lundholm.