Lewis, J. S. (1996). Rain of iron and ice: The very real threat of comet and asteroid bombardment. Addison-Wesley.
Dyfyniad Arddull ChicagoLewis, John S. Rain of Iron and Ice: The Very Real Threat of Comet and Asteroid Bombardment. Reading, Mass: Addison-Wesley, 1996.
Dyfyniad MLALewis, John S. Rain of Iron and Ice: The Very Real Threat of Comet and Asteroid Bombardment. Addison-Wesley, 1996.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.