There was an article written about Tsu in a Windsock magazine. I don't have it but I suspect it was translated in a french magazine (that I have somewhere...
at the time of Tsu first victories , N37's planes sported a dark (black? red?) circle on the fuselage with a letter in it. There is a picture of Nieuport 17 coded "T" that is supposedely Tsu's airplane.
I don't know anything von Melenthin but I am interested on Tsu' 1st victory on 10th july 1916. He shot down a plane behind german lines and the victory was confirmed, so there was witnesses on the ground that saw the plane crash. I read somewhere that Otto Parschau
was wounded that same day in the same area (Somme) and died of wounds on 21st july. Could it be?