Completed-Theses.md

 ## Supervised Theses (since Oct. 2014)
 
 ### PhD
+* *Development of scintillator detectors for measuring muons and air showers*
+(Christine Peters, Mai 2019, 3a)
+[[pdf](https://git.rwth-aachen.de/tbretz/research/raw/master/Theses/PhD/Christine Peters.pdf)]
 
 * *Exploring Silicon Photomultipliers for the Upgrade of the Pierre Auger Observatory*
 (Johannes Schumacher, September 2018, 3a)