The A to Z of inventions and inventors

["History" "Encyclopedias" "Inventions" "Inventors" "Biography" "Juvenile Science (General)" "Juvenile Nonfiction" "Children's Books/Ages 9-12 Fiction" "Children: Grades 3-4" "History - General" "Science & Nature - General" "Technology - How Things Work/Are Made" "Technology - Inventions" "20th century" "Inventions history"]