Adding author information and removing redundant word "PDF"

free-programming-books.md

@@ -1043,7 +1043,7 @@ Original Source: [List of freely available programming books](http://web.archive
 * [Cloudera Impala](http://www.cloudera.com/content/cloudera/en/resources/library/aboutcloudera/cloudera-impala-ebook.html) - John Russel
 * [Hadoop Illuminated](http://hadoopilluminated.com/book.php) - Mark Kerzner & Sujee Maniyam
 * [Programming Pig](http://chimera.labs.oreilly.com/books/1234000001811/index.html) - Alan Gates
-* [Data-Intensive Text Processing with MapReduce](http://lintool.github.io/MapReduceAlgorithms/MapReduce-book-final.pdf) (PDF)
+* [Data-Intensive Text Processing with MapReduce](http://lintool.github.io/MapReduceAlgorithms/MapReduce-book-final.pdf) (Jimmy Lin and Chris Dyer) (PDF)
 
 
 ### Haskell
@@ -1275,7 +1275,7 @@ See also [TeX](#tex)
 * [Secure Programming for Linux and Unix](http://www.dwheeler.com/secure-programs/Secure-Programs-HOWTO.html)
 * [The Debian Administrator's Handbook](http://debian-handbook.info/)
 * [The Linux Command Line](http://linuxcommand.org/tlcl.php) (PDF)
-* [The Linux Development Platform (PDF)](http://www.informit.com/content/downloads/perens/0130091154.pdf) (PDF)
+* [The Linux Development Platform](http://www.informit.com/content/downloads/perens/0130091154.pdf) (PDF)
 * [The Linux Kernel Module Programming Guide](http://tldp.org/LDP/lkmpg/2.6/html/)
 * [The Linux System Administrator's Guide](http://www.tldp.org/LDP/sag/html/index.html)
 * [OpenVZ Linux virtualization](http://download.openvz.org/doc/OpenVZ-Users-Guide.pdf) (PDF)