%% -*-BibTeX-*- @Article{AscheuerGroetschelAbdel-Hamid1999, author = "Norbert Ascheuer and Martin Gr{\"o}tschel and Atef Abdel-Aziz Abdel-Hamid", title = "Order picking in an automatic warehouse: Solving online asymmetric {TSP}s", journal = "Mathematical Methods of Operations Research", volume = "49", number = "3", pages = "501--515", year = "1999", classmath = "*90B30 90C35 90C90", language = "English", }