What two newspaper owners are known for yellow journalism?

Yellow Newspapers meaning papers that publish little real news and instead focus on eye-catching printing and sensational headlines became popular near the end of the 19th century. The New York World and the San Francisco Examiner were two of the most prominent Yellow Newspapers. 

Thomas Jefferson's idea of how slavery could be tolerated in a nation that trumpeted liberty had to do with the fact that he felt it was a "necessary evil" that must continue long enough for the US to develop properly. He felt as though blacks were inherently inferior and therefore needed "guidance".