general knowledge

http://www.ratnasagar.com/books/bookindex.aspx?MainID=M03

http://www.mylibrary.britishcouncil.org/action/content~search_genre/genre/508/

http://www.brainy-child.com/articles/children-general-knowledge.shtml

http://www.teksonsbooks.com/top/bestsellers.asp

http://www.mlbd.com/showBook.aspx?cat=133&id=373

http://www.nikithaonline.com/generalknowledge.php