updated contributors
diff --git a/contributors.md b/contributors.md
index 629f318..5b716b5 100644
--- a/contributors.md
+++ b/contributors.md
@@ -12,12 +12,14 @@
- [Adam Pauls](http://www.eecs.berkeley.edu/~adpauls/) (Berkeley)
- [Chris Callison-Burch](http://cs.jhu.edu/~ccb/) (Penn)
- [Chris Dyer](http://www.cs.cmu.edu/~cdyer/) (Carnegie Mellon)
+- [Chris Mattmann](http://sunset.usc.edu/~mattmann/) (APL, USC)
- [Colin Bannard](http://comp.ling.utexas.edu/~bannard/) (UT Austin)
- [Jonathan Weese](http://cs.jhu.edu/~jonny/) (Johns Hopkins)
- <li>Josh Schroeder (Edinburgh)</li>
+- Josh Schroeder (Edinburgh)
- [Juri Ganitkevitch](http://cs.jhu.edu/~juri/) (Johns Hopkins)
- [Kenneth Heafield](http://kheafield.com/) (Carnegie Mellon)
- [Lane Schwartz](http://dowobeha.github.com) (Minnesota)
+- [Lewis John McGibbney](https://github.com/lewismc) (NASA JPL)
- [Luke](https://plus.google.com/107547504293849335564) [Orland](https://github.com/lukeorland) (Johns Hopkins)
- [Matt Post](http://cs.jhu.edu/~post/) (Johns Hopkins)
- [Omar F. Zaidan](http://cs.jhu.edu/~ozaidan/) (Johns Hopkins)
