"Flight" Magazine has been scanned page by page to pdf files, and these are available on the web - to include all the WWI years and beyond. Prepare to waste endless hours browsing
The main site is:
Aviation History - Browse the History of Flight from 1909
For the Junkers J.I, 1920 pp 229-233, 262-265, 290-293, 315-318
Link to p.229
centre section | area | fuselage | 1920 | 0229 | Flight Archive
For the Benz BZ.IV, 1917 pp 1274-1278, 1309-1312,1331-1334. 1918 pp 746-747
Link to p. 1274
aero engine | german aero | pdf archive | 1917 | 1274 | Flight Archive
For the Junkers D.I, 1920 pp 376-380, 394-396, 419-422
Link to p.376
junker single-seater | centre section | area | 1920 | 0376 | Flight Archive