After using a source one time you can shorten the citation.
For Books:
Author's Last name, shorten title of the book in Italics, page number. ex. Millard, Destiny of the Republic, 54.
For Articles:
Author's Last Name, Title of Journal in Italics, page number. ex. Cook, The New England Quarterly, 302.
For an electronic resources such as a webpage depending on what information you actually have. For any source you could be missing information, but put as much as you can find.
