diff --git a/CITATION.cff b/CITATION.cff
new file mode 100644
index 0000000..db238a4
--- /dev/null
+++ b/CITATION.cff
@@ -0,0 +1,17 @@
+cff-version: 1.2.0
+message: "If you use this software, please cite it as below."
+authors:
+- family-names: "Delaporte-Mathurin"
+  given-names: "Rémi"
+  orcid: "https://orcid.org/0000-0003-1064-8882"
+- family-names: "Shimwell"
+  given-names: "Jonathan"
+  orcid: "https://orcid.org/0000-0001-6909-0946"
+- family-names: "Pranto"
+  given-names: "Ariful Islam"
+- family-names: "Faisal"
+  given-names: "Mohammed"
+title: "OpenMC Plasma Source"
+version: 0.2.2
+date-released: 2021-09-29
+url: "https://github.com/fusion-energy/openmc-plasma-source"
\ No newline at end of file
diff --git a/README.md b/README.md
index 49d8627..878fa6a 100644
--- a/README.md
+++ b/README.md
@@ -43,7 +43,7 @@ my_source = TokamakSource(
     shafranov_factor=0.44789,
     triangularity=0.270,
     ion_temperature_beta=6
-  )
+  ).make_openmc_sources()
 ```
 
 For a more complete example check out the [example script](https://github.com/fusion-energy/openmc-plasma-source/blob/better_readme/examples/tokamak_source_example.py).
@@ -57,9 +57,11 @@ For a more complete example check out the [example script](https://github.com/fu
 Create a ring source with temperature distribution of a 2000 eV plasma.
 
 ```python
+from openmc_plasma_source import FusionRingSource
+
 my_plasma = FusionRingSource(
-    start_angle = 0.,
-    stop_angle = 6.28318530718,  # input is in radians
+    angles = (0., 6.28318530718),  # input is in radians
+    radius = 400,  # units in cm
     temperature = 20000.,  # ion temperature in eV
     fuel='DT'  # or 'DD'
 )
@@ -70,6 +72,8 @@ Create a point source with temperature distribution of a 2000 eV plasma.
 
 
 ```python
+from openmc_plasma_source import FusionPointSource
+
 my_plasma = FusionPointSource(
     coordinate = (0, 0, 0),
     temperature = 20000.,  # ion temperature in eV