[1]
A. B. Grigoryan, “ALGEBRAIC MULTIGRID PRECONDITIONER FOR ELLIPTIC PROBLEMS WITH MIXED TYPE BOUNDARY CONDITIONS I. TWO-GRID PRECONDITIONERS”, Proc. YSU A: Phys. Math. Sci., vol. 40, no. 1 (209), pp. 37–48, Mar. 2006, doi: 10.46991/PYSUA.2006.40.1.037.