The .HEADERS case commands specify the case of the word "page"
    that precedes the page number. The commands .HEADERS UPPER,
    .HEADERS LOWER and .HEADERS MIXED produce, respectively, PAGE,
    page, and Page. In an index, these commands also affect the word
    "index" that is part of the page number, for example, Page Index-
    3. The command normally takes effect on the next page.

    Formats

      .HEADERS  UPPER

      .HEADERS  LOWER

      .HEADERS  MIXED

    Abreviated formats

      .HD  UPPER

      .HD  LOWER

      .HD  MIXED