The PDF documentation was not delivered with the source and thus it has
been removed to be able to ship the package in main. Upstream was
contacted about the source

You can find the documentation online here:

    PAML Manual:
       http://abacus.gene.ucl.ac.uk/software/pamlDOC.pdf

    PAML FAQs:
       http://abacus.gene.ucl.ac.uk/software/pamlFAQs.pdf

Feel free to find more information at the PAML homepage
       http://abacus.gene.ucl.ac.uk/software/paml.html

 -- Andreas Tille <tille@debian.org>  Mon, 02 May 2016 15:37:17 +0200