Create gesellschaft-fur-popularmusikforschung.csl
Update gesellschaft-fur-popularmusikforschung.csl

Now I solved the most problems, but the following 2 problems are not solved:

First: To alter „Hg. von“ into „Hg. v.“ (Under „locale“ I tried to create a new term „edited-by“, but this wasn’t useful (line 21)):

locale-edited-by.png

Second: The problem described on Nov. 04th:

R: I gave you wrong information. I want to realize the following two options (concerning bibliographic entries):

1.	Helms, Dietrich (2008). "What's the difference? Populäre Musik im System des Pop." In: PopMusicology. Perspektiven der Popmusikwissenschaft. (The latter titel is in italics!) Hg. v. Christian Bielefeldt, Udo Dahmen u. Rolf Großmann. Bielefeld: Transcript.
2.	Bielefeldt, Christian / Grossmann, Rolf / Dahmen, Udo (Hg.) (2008): PopMusicology. Perspektiven der Popmusikwissenschaft. (The latter titel is in italics!) Bielefeld: Transcript.

I have a problem with the editor names: I don't manage to divide the following two options: First: If the entry is a single book chapter or similar type, the editor names must appear after the title and in the order indicated above under (1.). Second: If the entry is the whole edited book, the editor names must appear before the title and in the order indicated above unter (2.).
Another problem is the delimiter "," in case (1.): I want to put the delimiter "u." only between the last two names. All names before must be divided with the delimiter ",".
Update gesellschaft-fur-popularmusikforschung.csl
Update gesellschaft-fur-popularmusikforschung.csl
Update gesellschaft-fur-popularmusikforschung.csl

Now there remains only 1 error: (line 140) <label variable=" " form="short"/>"

The problem is: In citations I don't want to use a label in front of the page numbers!
Update gesellschaft-fur-popularmusikforschung.csl

Dear all! Thanks a lot for your comments and aid! Now there are no errors, I think! 

The only problem remaining is the "delimiter" in container titles: If the entry is a book chapter, I want to have the "u." only before the last editor name. All names before should be devided with ",". In the following examples the second version is the right one:

(1) Großmann, Rolf (2008). „Die Geburt des Pop aus dem Geist der phonographischen Reproduktion.“ In: PopMusicology: Perspektiven der Popmusikwissenschaft. Hg. v. Christian Bielefeldt u. Udo Dahmen u. Rolf Grossmann. Bielefeld: Transcript, S. 119–134.

(2) Großmann, Rolf (2008). „Die Geburt des Pop aus dem Geist der phonographischen Reproduktion.“ In: PopMusicology: Perspektiven der Popmusikwissenschaft. Hg. v. Christian Bielefeldt, Udo Dahmen u. Rolf Grossmann. Bielefeld: Transcript, S. 119–134.
Update gesellschaft-fur-popularmusikforschung.csl

My last update with no errors, I believe.
Update gesellschaft-fur-popularmusikforschung.csl

@zuphilip and @adam3smith: I changed all options concidering your suggestions two days ago. It seems to look very good now, and the validation didn't found any errors. Thanks a lot again!
Merge pull request #1221 from helmy20/patch-3

Create gesellschaft-fur-popularmusikforschung.csl