Dang, Thanh Tung, Baltazár Frankovic, Ivana Budinská, Ben Flood, Con Sheahan, and Bao Lam Dang. 2012. “Using Heuristic Search for Solving Single Machine Batch Processing Problems”. Computing and Informatics 25 (5):405-20. http://147.213.75.17/ojs/index.php/cai/article/view/351.