In the Jagdstaffel Boelcke lineup of Fokker Dr.Is, photo B/3 on page 7 of Greg VanWyngarden's "Fokker Dr.I Jagdstaffeln", is the white X marked triplane that of Ltn.d.R.
Karl Gallwitz? Note the leader's streamer visible on the starboard wing underneath fuselage Eisenkreuz. On the same page, photo B/4 shows a frontal view of Gallwitz's triplane 212/17 complete with leader's streamers with Gallwitz and his mechanics unfortuantely blocking the view of possible fuselage markings.