diff --git a/README.md b/README.md
index a927699..e629ca0 100644
--- a/README.md
+++ b/README.md
@@ -7,101 +7,101 @@ These Python programs can be downloaded from GitHub at
 
 
 
-DWH.py
+DWH.py: 
 	Biased double well.
 
-DampedDriven.py
+DampedDriven.py: 
 	Driven-damped oscillators.  Options are: driven-damped pendulum and driven-damped double well potential.  Plots a two-dimensional Poincaré section.
 
-DoublePendulum.py
+DoublePendulum.py: 
 	Double pendulum.
 
-Duffing.py
+Duffing.py: 
 	Duffing oscillator.
 	
-FlipPhone.py
+FlipPhone.py: 
 	Flipping iPhone simulator. (See https://galileo-unbound.blog/2021/10/10/physics-of-the-flipping-iphone-and-the-fate-of-the-earth/.)
 
-Flow2D.py
+Flow2D.py: 
 	Simple flows for 2D autonomous dynamical systems.  Options are: Medio, van der Pol, and Fitzhugh-Nagumo models.
 
-Flow2DBorder.py
+Flow2DBorder.py: 
 	Same as Flow2D.py but with initial conditions set on the boarder of the phase portrait.
 
-Flow3D.py
+Flow3D.py: 
 	Flows for 3D autonomous dynamical systems.  Options are: Lorenz, Rössler and Chua’s Circuit.
 	
-GravSynch.py
+GravSynch.py: 
 	Synchronization of clocks in a spaceship near a black hole.  (See: https://galileo-unbound.blog/2021/05/16/locking-clocks-in-strong-gravity/)
 
-gravlens.py
+gravlens.py: 
 	Gravitational lensing.  (See: https://galileo-unbound.blog/2021/04/05/the-lens-of-gravity-einsteins-rings/)
 
-Hamilton4D.py
+Hamilton4D.py: 
 	Hamiltonian flows for 4D autonomous systems.  Options are: Henon-Heiles potential, and the crescent potential.  Plots a two-dimensional Poincaré section.
 
-Heiles.py
+Heiles.py: 
 	Henon-Heiles and also a crescent model
 
-HenonHeiles.py
+HenonHeiles.py: 
 	Standalone Henon-Heiles model.
 
-Hill.py
+Hill.py: 
 	Hill potentials for 3-body problem.
 
-Kuramoto.py
+Kuramoto.py: 
 	Kuramoto synchronization of phase oscillators on a complete graph.
 
-logistic.py
+logistic.py: 
 	Logistic discrete map, plus some other choices.
 
-Lozi.py
+Lozi.py: 
 	Discrete iterated Lozi map conserves volume.
 
-NetDynamics.py
+NetDynamics.py: 
 	Coupled phase oscillators on various network topologies.  Has more options than coupleNdriver.py.
 
-NetSIR.py
+NetSIR.py: 
 	SIR viral infection model on networks
 
-NetSIRS.py
+NetSIRS.py: 
 	SIRS viral infection model on networks
 
-PenInverted.py
+PenInverted.py: 
 	Inverted pendulum. (See: https://galileo-unbound.blog/2020/09/14/up-side-down-physics-dynamic-equilibrium-and-the-inverted-pendulum/)
 
-Perturbed.py
+Perturbed.py: 
 	Driven undampded oscillators with a plane-wave perturbation.  Options are: pendulum and double-well potential.  These are driven nonlinear Hamiltonian systems.  When driven at small perturbation amplitude near the separatrix, chaos emerges.  These systems do not conserve energy, because there is a constant input and output of energy as the system reacts against the drive force.  Plots a two-dimensional Poincaré section.
 
-raysimple.py
+raysimple.py: 
 	Eikonal equation simulator.
 
-SIR.py
+SIR.py: 
 	SIR homogeneous COVID-19 model
 
-SIRS.py
+SIRS.py: 
 	SIRS homogeneous COVID-19 model
 
-SIRWave.py
+SIRWave.py: 
 	Covid-19 second wave model
 
-StandMap.py
+StandMap.py: 
 	The Chirikov map, also known as the standard map, is a discrete itereated map with winding numbers and islands of stability.
 
-StandMapHom.py
+StandMapHom.py: 
 	Homoclinic tangle for the standard map.
 
-StandMapTwist.py
+StandMapTwist.py: 
 	The Standard Map in twist format
 
-trirep.py
+trirep.py: 
 	Replicator dynamics in 3D simplex format.
 
-UserFunction.py
+UserFunction.py: 
 	Growing library of user functions
 		linfit.py – linear regression function
 
-WebMap.py
+WebMap.py: 
 	The discrete map of a periodically kicked oscillator displays a web of dynamics.  (See: https://galileo-unbound.blog/2018/10/27/how-to-weave-a-tapestry-from-hamiltonian-chaos/)
 
 (Selected Python programs can be found at the Galileo Unbound Blog Site: