Morning all,
Is it a Rumpler C.III ?
The C.I appears to more of a sesquiplane, I don't think they buit any II's and the C.IV had elliptical tips on the lower wings. I think that one III had a different engine fitted for an altitude attempt.
Helluva day yesterday, couldn't get any free time at all.
Back to work now, so OH in the unlikely event of it being correct!