Jean-Louis Bouquard Jean-Charles Billaut Mikhail A. Kubzin Vitaly A. Strusevich Two-machine flow shop scheduling problems with no-wait jobs. 255-262 2005 33 Oper. Res. Lett. 3 http://dx.doi.org/10.1016/j.orl.2004.06.003 db/journals/orl/orl33.html#BouquardBKS05