Forcing pagebreaks in multi-score book

[Your Name]

Lilypond 2.5.25 Windows.

Excellent that we finally have a 2.5 version for Windows. 
I am starting to assemble a book whilch will be made up of 
many separate files put together like this:

\book {
  \header {
    title = "Book title"
  }
  \score { \include "file1" }
  \score { \include "file2" }
  ...
}

And where each file contains something like
\header {
  title = "Score title"
}
{ music }

Now, I need a way to force a page preak between any of the scores.
Since the included files can be put together in any order for different
books, I cannot use breakbefore = ##t in the file header fields.

At first I thought I might put a 
\score { \header { breakbefore = ##t } {} }
but that doesn't work. \score {{ \pageBreak }} doesn't work either.
I need something that generates only the page break, and no score 
lines or 
anything.

-- 
Sven Axelsson, Sweden