U.S.-Air-Force-Phillips-Laboratory.-The-major-magnetic-storm-of-March-13-14-1989-and-associated-ionosphere-effects.-GMD-October-1-1991-pdf Continue Reading Previous U.S.-Air-Force-Phillips-Laboratory.-The-major-magnetic-storm-of-March-13-14-1989-and-associated-ionosphere-effects.-GMD-October-1-1991-pdf