Walker G. (2003). Snowball earth: The story of the great global catastrophe that spawned life as we know it. Three rivers.
Чикаго маягийн жагсаалтWalker G. Snowball Earth: The Story of the Great Global Catastrophe That Spawned Life as We Know It. USA: Three rivers, 2003.
MLA ишлэлWalker G. Snowball Earth: The Story of the Great Global Catastrophe That Spawned Life as We Know It. Three rivers, 2003.
Warning: These citations may not always be 100% accurate.