Mate you should be looking into German Metal Detecting forums, at best there is just a couple people on here I can think of that may be able to point you in the right direction. I have found 7 bronze axe heads and 2 bronze spear points in my time in Europe. One has the same cross on it and I found that in Lithuania, all my bronze came out of Lithuania or Latvia. But I have never found any information on it at all.
I would suggest either going to a German MDing forum or doing a google picture search for Alte Beile or Alte Äxte.
I will tell you that the first thing that will come up will be two books in German, do not buy them, I own them and the trademark is not in either of them.
If you find out come back and let us know, heck I would love to know, I have a nice blade collection and that trademark I have never figured out.