Okada, Y.; Kasahara, K. (1990). "Earthquake of 1987, off Chiba, central Japan and possible triggering of eastern Tokyo earthquake of 1988". Tectonophysics. 172 (3–4): 351–364. Bibcode:1990Tectp.172..351O. doi:10.1016/0040-1951(90)90041-6.
Okada, Y.; Kasahara, K. (1990). "Earthquake of 1987, off Chiba, central Japan and possible triggering of eastern Tokyo earthquake of 1988". Tectonophysics. 172 (3–4): 351–364. Bibcode:1990Tectp.172..351O. doi:10.1016/0040-1951(90)90041-6.