add state of the art

references.bib

@@ -71,7 +71,7 @@
     number={1},
     pages={82-88},
     doi={10.1109/TCIAIG.2014.2331972},
-    keywords="videojuegos,prolog"
+    keywords="ai,videojuegos,prolog"
 }
 
 @ONLINE{GDNative-Benchmarks,
@@ -93,5 +93,15 @@
 @ARTICLE{mccarthy2007artificial,
     author={McCarthy, John},
     title={What is artificial intelligence?},
-    year={2007}
+    year={2007},
+    keywords="ai"
+}
+
+@ARTICLE{FerreinJacobsLakemeyer2011,
+  autho={Alexander Ferrein and Stefan Jacobs and Gerhard Lakemeyer},
+  title={Controlling Unreal Tournament 2004 Bots with the logic-based action language Golog / Jacobs, Stefan ; Ferrein, Alexander ; Lakemeyer, Gerhard},
+  journal={Proceedings of the First AAAI Conference on Artificial Intelligence and Interactive Digital Entertainment (AIIDE).},
+  pages={151 -- 152},
+  year= {2011},
+  keywords="ai,prolog,videojuegos"
 }