I am afraid I do not have any really good references, but I have noticed that contemporary newspapers covered the eastern front as best they could. As an example, there are a number of clippings in New York newspapers refered to here
. (Scroll down to the section "World War I in the Bukowsko Area". This is in Galicia rather than Bukowina, which is a bit to the east, but may be relevant.
You may also have read the memoirs of Fritz Kreisler, the violinist, which are available here
. This also deals with Galicia, but should give us the flavour of the campaign in those areas.
I am afraid this is the best I can do just now.