Last Name, First Name (Author). Title of the book. Place of publication: Publisher. Year.

Macdonald, Fiona. The Middle Ages. England: Simon and Schuster Young Books. 

Web page:

Last Name, First Name (Author). "Title of page or article." Title of complete work. Date
        last updated. URL. Date you visited.

"Crusades." Wikipedia, the free encyclopedia. February 9, 2011.
         wiki/Crusade#List_of_crusades. March 7, 2012.