X-Class Soft X-ray Bursts and Major Proton Events During Solar Cycle 22 (1987-1991) Gentile, L. C. ; Campbell, J. M. ; Cliver, E. W. ; Cane, H. V. Abstract Publication: Solar-Terrestrial Predictions -- IV, Volume 2 Pub Date: 1993 Bibcode: 1993stp2.conf..153G