Surely a symphony by Haydn, but what symphony?

[Enrique]

The theme is this, that has stuck on my mind:



Any ideas?

[Enrique]

OK. I finally realized it is Schubert, not Haydn. It's from the Schubert's fifth symphony, in B flat major, the andante. I must have been drinking some strange beverage lately. And it's 6/8, not 3/4.