I wanted to share what I think is wonderful, "Cello Concerto in C minor" by Ricardo Castro (1864-1907).
Ricardo Castro was a Classical composer and concert pianist in Mexico. Sorry, I couldn't easily find sheet music for this particular piece, but a link to more info.
The Castro cello concerto is one of the most unjustly neglected pieces for cello; I think it should be standard repertoire. But I don't think it was published until the 1980s. It was performed once in Paris while the composer was alive, and then the second performance (and first in Mexico) was not until 1981.
(EDIT: for some reason I had the year 1978 in my mind with regard to the second performance of this concerto. Maybe I saw something about it being rediscovered in 1978? The second performance was in 1981.)