Sofia: Bulgarian State Publishing House, 1957.
Public Domain [tag/del]
Possibly the same work as the C major cello concerto WeiV 2d. C1? (See RISM 600026005. Also, I think the latter work has been recorded - at least one of his cello concertos in that key has- so the viola part can be followed while listening to the recording for comparison.)
Movements are Allegro moderato , Adagio, Allegro moderato in the 1957 edition though not necessarily in the original.
Two Vanhal viola concertos have been published:
in F Vienna: Doblinger, c. 1978. ed Weinmann, Alexander, Karl Trotzmuller
in C Prague:Artia/Supraphon 1973 ed V. Blazek & J. Plichta Musica Viva Historica No.10