EUROCONTROL has published Version 2 of the European Action Plan for Airspace Infringement Risk Reduction, March 2022
https://skybrary.aero/articles/european-airspace-infringement-action-pl…

Airspace infringement, also known as “unauthorised penetration of airspace”, is a major operational hazard that can result from the division of airspace into different classes and structures, with their associated procedures and services, and its joint use by different categories of users - including GA pilots, often with competing objectives and different operational requirements and capabilities.

Other references relevant for GA pilots and instructors:

EASA and Safety Promotion Network (SPN) Airspace Infringement Campaign:
https://www.easa.europa.eu/domains/general-aviation/flying-safely/airsp…

Sunny Swift Editions 19 and 20 Airspace Complexity:
https://www.easa.europa.eu/community/topics/sunny-swift-edition-19-airs…;
https://www.easa.europa.eu/community/topics/sunny-swift-edition-20-airs…

SKYbrary Airspace Infringement: Guidance Notes for GA Pilots
https://skybrary.aero/articles/airspace-infringement-guidance-notes-ga-…