Bacchus, Fahiem, Jessica Davies, Maria Tsimpoukelli, and George Katsirelos. “Relaxation Search: A Simple Way of Managing Optional Clauses”. Proceedings of the AAAI Conference on Artificial Intelligence 28, no. 1 (June 21, 2014). Accessed September 21, 2024. https://ojs.aaai.org/index.php/AAAI/article/view/8849.