D. Davis, T. Yuen, and M. Berland. Proceedings of the 45th ACM technical symposium on Computer science education, page 325--330. New York, NY, ACM, (2014)
L. Heels, and M. Devlin. Proceedings of the 3rd Conference on Computing Education Practice, page 2:1-2:4. New York, NY, ACM, (2019)https://doi.org/10.1145/3294016.3294028.