My best guess for the text below BÜLOW is "Deutsche Flugzeug Werke (newline) Leipzig". [![enter image description here][1]][1] Having three pairs of struts on each wing would make it a [DFW B.I][2], C.I or C.II, as later models only had two pairs of them. [![http://flyingmachines.ru/Site2/Crafts/Craft25582.htm][3]][3] The small gap between the wings matches the photo too. While some [prototypes got a machine gun][4], the standard version of the DFW B.I was unarmed. According to the book "German Aircraft of the First World War" (Peter Gray & Owen Thetford) the only difference between the C.I and C.II version is the position of the pilot (C.I: pilot in rear seat). Another [source][5] mentions the change of the machine gun from Parabellum to a synchronized one. A synchronization gear only makes sense attached to a fixed machine gun below the upper wing. With a gun over the upper wing and assuming that Bülow is sitting in the pilot's seat, I'd say that the airplane is a DFW C.I. [1]: https://i.sstatic.net/zhad0.png [2]: https://en.wikipedia.org/wiki/DFW_B.I [3]: https://i.sstatic.net/tEQsTm.png [4]: https://de.wikipedia.org/wiki/DFW_B-Typen#Weiterentwicklung [5]: http://www.airwar.ru/enc/other1/dfwc1.html