I have three .tex files that get compiled fine using polyglassia & xelatex packages. When I combine these three tex files in one tex file, it exceeds the memory due to a lot of special fonts used in them. So I ended up compiling them separately. As a result, I have three PDF outputs that contain hyperlinked pages to their TOC, and hyperlinked sections in TOC. So, there are three PDF's, thus three Table of Contents for each PDF.
How do I combine these PDF's preserving hyperlinks as well as having one TOC file [preferably in a single multi-column page]?