Hello,
I’m curious if I can use multiple page templates in one document and how to change the page’s template without changing it for other pages.
The reason is that I want a two-columns-layout for the main content and a single-column-layout for the sources etc.
Thank you for your help 
btw, I found this documentation but it didn’t worked in my document (Windows 10 64-bit, LO 5.3.3.2).
Whar is it, that doesn’t work for you? Defining a page style?
No, I can define multiple page styles (like I would define paragraph styles), but I can’t get them working (so that the current page has my new page style).
More details needed. What do you want exactly? What is that you can’t achieve?
You can have more then one page templates ‒ use page styles!
One page style should have single column layout and second should have two column layout. You’re switching them using page brakes.
Apply two column layout on your first page. Enter your content. When need single column layout, use
Insert ‒ Manual break... ‒ Page break
and select page style from a drop down. Presumably single column layout. That’s it! Do this again when other page style needed.
Page styles are templates, you just need to know how to switch between them without changing them.
Mark this question answered if this is what you are looking for. Comment if need additional help.
You’re switching them using page brakes.
Breaks may be or may not be needed if you properly organize styles. Depends on the situation.
I agree, but manual brakes give, well, more control. And if I got everything correctly, manual breaks are a way to go.
Hi,
thank you for your answer, it worked 
But now I’ve got another answer: If I got 3 pages, each with a certain page-style, and I want to move page 1 to the end of the document (with it’s content & page-style), how can I do this without breaking the whole document?
You can’t move pages actually. You can move texts. Thus, move the text that you need and insert page breaks as appropriate.
ok, thank you all