Hello Joao,
You're right. In
Bloody April ......Black September you can read that "Büchner was in action again at 17.56, the 94th getting into a fight with Jasta 13. Although the 94th were credited with a Fokker, Lieutenant Alan Nutt was shot down, followed by Lieutenant Alan B. Sherry.
His shot up Spad crash-landed in 'no-man's-land, where he remained until the following day.
This brought Büchner's score to 36. In the fortnight since the 12th, he had claimed 14 victories-mostly Americans."
Hope this helps,
Jos