Inc. BarCharts 
Earth [PDF ebook] 

Our planet has inspired a sense of awe since the dawn of humankind, and scientists are learning more about it every day. Even if you’re not a scientist, pick up the new Earth Quick Study(R) guide and get your research started. This guide is packed with interesting facts and explanations, from Earth’s location in space to its inner core, and written with a perfect balance of science, real-world examples, and fun facts.