--- a/doc/kishna.tex	Mon Dec 08 21:00:50 2008 +0000
+++ b/doc/kishna.tex	Mon Dec 08 21:15:52 2008 +0000
@@ -162,7 +162,16 @@
 normal. Picture explains this a lot.
 
 \subsection{Physics}
-runge kutta, something network related?
+
+The fourth-order Runge-Kutta method is a numerical method for
+approximating the solution of an ordinary differential equation. In
+our game the Runge-Kutta method is used to calculate positions and
+velocities of physics objects when we apply forces to them.
+
+% TODO: Here we could write the runge kutta method mathematically
+% (copy paste from wikipedia or something)
+
+something network related?
 
 \section{Known bugs}
 A lots of them (or maybe not).
@@ -176,7 +185,9 @@
 
 % References
 \begin{thebibliography}{99}
-\bibitem{foo} Foo reference
+\bibitem{gaffer} Gaffer on games. Game
+  Physics. 2006. http://gafferongames.wordpress.com/game-physics/
+  (read: 2008-12-08)
 \end{thebibliography}
 
 \end{document}

--- a/doc/mkpdf.sh	Mon Dec 08 21:00:50 2008 +0000
+++ b/doc/mkpdf.sh	Mon Dec 08 21:15:52 2008 +0000
@@ -1,3 +1,3 @@
 #!/bin/sh
 latex kishna.tex
-dvipdf kisgna.dvi
+dvipdf kishna.dvi