I want to read a proof of the following theorem of Wielandt,
Theorem: Let $G$ be a finite group and let $P\in Syl_p(G)$ such that $P$ is regular. Then $N_G(P)$ controls $p$-transfer.
I found a proof of this theorem, but it is written in German (which I can not speak). Is there any English version of this proof?
It is also welcome to give a proof here.
Note: the proof is in Endliche Gruppen I" by Bertram and Huppert, chapter IV, part 8 (page 447)