World Book presents a universe of information. From A to Z, the world of knowledge unfolds. World Book articles are written clearly. They're concise and interesting...packed with facts instead of adjectives. And because each article is tightly written, there are more of them in each volume.

• Authored and edited by 3,700 experts
• Checked and rechecked
• Updated more than any other reference source
• Straightforward and understandable to students of all ages and levels.

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Since 1917,World Book, Inc., has set the standard for providing accuracy, objectivity, and reliability in research materials for both children and adults. Based in Chicago, Illinois, World Book is an industry leader in the production of award-winning encyclopedias, reference sources, and multimedia products for the home and schools. For over eighty years, World Book has been committed to publishing encyclopedias and references that meet the highest standards of editorial excellence while keeping pace with the technological developments that define the computer age. To learn more about World Book's products and services please visit www.worldbook.com.