I bought this one in a flea market in Rome. There is no clear brand but it is obviously a well constructed camera. A "sticker" that is peeling off shows part of a pigeon or something alike. The lens is an Emil Busch Omnar Anastigmatic f4.5 - 25.5 cm. I have as a project to make some glass negatives to use with it. So far I only tried some normal negatives but a field camera like this is something that one must really dedicate to start getting some good results.
Here is the label. Any clue about producer or whatever is appreciated.