\markboth
---------
\markboth{left head}{right head}
The `\markboth' command is used in conjunction with the page style
`myheadings' for setting both the left and the right heading. You
should note that a "left-hand heading" is generated by the last
`\markboth' command before the end of the page, while a "right-hand
heading" is generated by the first `\markboth' or `\markright' that
comes on the page if there is one, otherwise by the last one before the
page.