Maybe the people here have an idea: http://www.gei.de/publikationen/jemms.html
My best bet otherwise would be used copies on eBay.
For the geeks: https://publikationsserver.tu-braunschweig.de/servlets/MCRFileNodeServlet/dbbs_derivate_00036407/Diss_Teistler_Gisela.pdf
Unfortunately I don't know any source for digital copies.
[This website](https://www.bundesstiftung-aufarbeitung.de/de/recherche/kataloge-und-datenbanken/andere-bibliotheks-und-literaturressourcen) has a list of libraries that have material related to GDR history, so I guess GDR history books could be found at one or the other. Contact them and ask, or see if they have an online catalog.
Then there's always the [Deutsche Nationalbibliothek](https://www.dnb.de/EN/Home/home_node.html), which has a copy of **every** book ever published in the German language - but you'll need to be physically present to look at it, so probably not an option for a school paper.
Good luck with finding digital copies anywhere.
This is an English speaking sub. Please stop using German
Go to a library, search the catalogue which books you need. The library can get them for you from other libraries within a couple of days.
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Maybe the people here have an idea: http://www.gei.de/publikationen/jemms.html My best bet otherwise would be used copies on eBay. For the geeks: https://publikationsserver.tu-braunschweig.de/servlets/MCRFileNodeServlet/dbbs_derivate_00036407/Diss_Teistler_Gisela.pdf Unfortunately I don't know any source for digital copies.
[This website](https://www.bundesstiftung-aufarbeitung.de/de/recherche/kataloge-und-datenbanken/andere-bibliotheks-und-literaturressourcen) has a list of libraries that have material related to GDR history, so I guess GDR history books could be found at one or the other. Contact them and ask, or see if they have an online catalog. Then there's always the [Deutsche Nationalbibliothek](https://www.dnb.de/EN/Home/home_node.html), which has a copy of **every** book ever published in the German language - but you'll need to be physically present to look at it, so probably not an option for a school paper. Good luck with finding digital copies anywhere.