Does someone have an idea what these are? 
Is one AGO C.I 

General characteristics
Crew: two, pilot and observer 
Length: 9.0 m (29 ft 6 in) 
Wingspan: 15.0 m (49 ft 2 in) 
Wing area: 41.5 m² (447 ft²) 
Powerplant: 1 × Mercedes D.III, 117 kW (158 hp) 
Performance
Maximum speed: 140 km/h (90 mph) 
Range: 480 km (300 miles) 
Service ceiling: 4,800 m (16,000 ft) 
Armament
1 × 7.92 mm Parabellum machine gun