COLREGs-based Situation Awareness for Marine Vessels - a Discrete Event Systems Approach⁎This research is sponsored by the The Danish Maritime Fund, Orients Fund and the Lauritzen Foundation through the ASAN project: Autonomous Situation Awareness for Navigation, and by the Autonomy part of the Shipping Lab project, which is sponsored by the Danish Innovation Fund and the aforementioned Foundations. Issue 2 (2020)