diff --git a/docs/README.rst b/docs/README.rst
index 35c3d27..c5664b9 100644
--- a/docs/README.rst
+++ b/docs/README.rst
@@ -40,6 +40,21 @@ Example
   pyargs = {'m':m, 's':s, 'e':e, 'e_assoc':eAB, 'vol_a':volAB}
   den = pcsaft_den(t, p, x, pyargs, phase='liq')
   print('Density of water at {} K:'.format(t), den, 'mol m^-3')
+  
+  # Water using 4C association scheme
+  x = np.asarray([1.])
+  m = np.asarray([1.2047])
+  e = np.asarray([353.95])
+  volAB = np.asarray([0.0451])
+  eAB = np.asarray([2425.67])
+  assoc_schemes = ['4c']
+
+  t = 274
+  p = 101325
+  s = np.asarray([2.7927 + 10.11*np.exp(-0.01775*t) - 1.417*np.exp(-0.01146*t)]) # temperature dependent sigma is used for better accuracy
+  pyargs = {'m':m, 's':s, 'e':e, 'e_assoc':eAB, 'vol_a':volAB, 'assoc_scheme':assoc_schemes}
+  den = pcsaft_den(t, p, x, pyargs, phase='liq')
+  print('Density of water at {} K:'.format(t), den, 'mol m^-3')
 
 Dependencies
 ------------