Index: src/external.inc
===================================================================
--- src/external.inc	(revision 110)
+++ src/external.inc	(working copy)
@@ -160,9 +160,9 @@
     rho = pow(press/TOV_K[star], 1.0/TOV_Gamma[star]);
     gxx = r / (r_to_star + 1.0e-30) * r / (r_to_star + 1.0e-30);
     psip = pow(gxx, TOV_Momentum_Psi_Power/4.);
-    w_lorentz_2 = 1. - gxx*TOV_Velocity_x[star]*TOV_Velocity_x[star]
-                     - gxx*TOV_Velocity_y[star]*TOV_Velocity_y[star]
-                     - gxx*TOV_Velocity_z[star]*TOV_Velocity_z[star];
+    w_lorentz_2 = 1./(1 - gxx*TOV_Velocity_x[star]*TOV_Velocity_x[star]
+                             - gxx*TOV_Velocity_y[star]*TOV_Velocity_y[star]
+                             - gxx*TOV_Velocity_z[star]*TOV_Velocity_z[star]);
     rho_eps = w_lorentz_2 * rho +
               w_lorentz_2*TOV_Gamma[star]/(TOV_Gamma[star]-1.) * press;
     switch(dir)