Tractability-preserving transformations of global cost functions. - Allouche, David; Bessiere, Christian; Boizumault, Patrice; de Givry, Simon; Gutierrez, Patricia; Lee, Jimmy H.M.; Leung, Ka Lun; Loudni, Samir; Métivier, Jean-Philippe; Schiex, Thomas; Wu, Yi (Artificial Intelligence, 2016)