Scribus is an desktop open source page layout program with the aim of producing commercial grade output in PDF and Postscript, primarily, though not exclusively for Linux.
While the goals of the program are for ease of use and simple easy to understand tools, Scribus offers support for professional publishing features, such as CMYK color, easy PDF creation, Encapsulated Postscript import/export and creation of color separations.
sudo apt-get install scribus