AmgX: A Library for GPU Accelerated Algebraic Multigrid and Preconditioned Iterative Methods. - Maxim Naumov; M. Arsaev; Patrice Castonguay; Jonathan M. Cohen; Julien Demouth; Joe Eaton; Simon K. Layton; N. Markovskiy; István Z. Reguly; Nikolai Sakharnykh; V. Sellappan; Robert Strzodka (SIAM J. Sci. Comput., 2015)