Identification of magazine

[A.Mifsin]

I have two magazines which to me are a bit of a puzzle according to what I think I have understood (I hope). I am posting two photos of what is my interpretation of these magazine.
The first magazine looks like an Erfurt yellowish body magazine, but from the stop stamp it is a DWM and from the follower button it is an Erfurt.
The second magazine it has what I think is the DWM old style of number stamping on the bottom, (vertical numbers), the follower button is DWM. It is also a Navy type bottom, but the stop stamping is Erfurt.
Am I confusing issues or there is another explanation to this?

Another question. Am I correct to think that Mauser used the DWM stop stamping and Simson the erfurt stamping ? Thanks.
Alf.