Q: Glue 2 documents, rename all labels in one of them I need to combine several documents into one. Unfortunately both documents started e.g the equation labeling by \label{eq:1}. Is there a neat way to work with both TeX files and are cross references allowed? 
Or does one need to rename all labels and refs? Since I'm using emacs the auto replace would probably do this but I'm wondering if there is a more intelligent way instead of renaming everything bruteforce :)

A: Before to merge the two file, open one in emacs.
Use M-x replace-regexp RET eq:\([A-Za-z0-9]+\) RET eqA:\1
It will add a A after each eq. In this case even if you have the same label for two equations in the final file you'll have no errors. 
This supposed that each label you've wrote is constructed as eq:XX you can modify the regexp to match other construction.
