Corrected citation year

README.txt

@@ -210,7 +210,7 @@ Citing SimpleMOC-kernel
 Papers citing SimpleMOC-kernel should in general refer to:
 
 John R. Tramm, Geoffrey Gunow, Tim He, Kord S. Smith, Benoit Forget, 
-Andrew R. Siegel, (2015) "A task-based parallelism and vectorized approach
+Andrew R. Siegel, (2016) "A task-based parallelism and vectorized approach
 to 3D Method of Characteristics (MOC) reactor simulation for high performance
 computing architectures", Computer Physics Communications, Volume 202, 
 Pages 141–150, (https://doi.org/10.1016/j.cpc.2016.01.007).