Internal Program Version: PSUtils  p17

PSUtils is a collection of useful utilities for manipulating
PostScript documents. Programs included are psnup, for placing
out several logical pages on a single sheet of paper, psselect,
for selecting pages from a document, pstops, for general
imposition, psbook, for signature generation for booklet
printing, and psresize, for adjusting page sizes.

http://knackered.org/angus/psutils