Use secondary sources of information to find out the answer ... (Start by looking at evidence you trust – such as BBC Bitesize, textbooks you use in school or your parents, carers and teachers.) ...

Primary sources have not been filtered, but secondary sources have been filtered. Examples of secondary sources include biographies, textbooks, documentaries, encyclopedias, books. What was going on ...

House Bill 62 would require colleges to look for open-source materials for College Credit ... Ohio University purchases textbooks in bulk, passing on the savings to students and secondary schools, ...