De Giacomo, G., Y. Lespérance, and E. Ternovska. “ElGolog: A High-Level Programming Language With Memory of the Execution History”. Proceedings of the AAAI Conference on Artificial Intelligence, vol. 34, no. 03, Apr. 2020, pp. 2806-13, doi:10.1609/aaai.v34i03.5669.