diff --git a/LICENSE b/LICENSE
index c4d24aa..722b3db 100644
--- a/LICENSE
+++ b/LICENSE
@@ -1,6 +1,6 @@
 MIT License
 
-Copyright (c) 2017 Robert Litterman, Kent Daniel, Gernot Wagner
+Copyright (c) 2018 Robert Litterman, Kent Daniel, Gernot Wagner
 
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal
@@ -18,4 +18,4 @@ FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
-SOFTWARE.
\ No newline at end of file
+SOFTWARE.
diff --git a/README.md b/README.md
index e41849c..bd249e8 100644
--- a/README.md
+++ b/README.md
@@ -11,6 +11,8 @@ See the [EZ-Climate User's Guide](https://oscarsjogren.github.io/dlw/) for EZ-Cl
 
 In order to get the tip documentation, change directory to the `docs` subfolder and type in `make html`, the documentation will be under `../../ez_climate_docs/html`. You will need [Sphinx](http://sphinx.pocoo.org) to build the documentation.
 
+See [Applying Asset Pricing Theory to Calibrate the Price of Climate Risk](https://gwagner.com/daniel-litterman-wagner-applying-asset-pricing-theory-to-calibrate-the-price-of-climate-risk/) for the latest working paper employing this code.
+
 ## Installation
 
 We encourage you to use pip to install ezclimate on your system. 
diff --git a/ezclimate/bau.py b/ezclimate/bau.py
index 70d3732..61109de 100755
--- a/ezclimate/bau.py
+++ b/ezclimate/bau.py
@@ -127,7 +127,7 @@ def bau_emissions_setup(self, tree):
 
         for n in range(1, num_periods):
             self.emission_by_decisions[n] = self.emission_by_time(tree.decision_times[n])
-            self.emission_per_period[n] = period_len[n] * (self.emission_by_decisions[n-1:n].mean())
+            self.emission_per_period[n] = period_len[n-1] * (self.emission_by_decisions[n-1] + self.emission_by_decisions[n]) / 2
 
         #the total increase in ghg level of 600 (from 400 to 1000) in the bau path is allocated over time
         self.emission_to_ghg = (self.ghg_end - self.ghg_start) * self.emission_per_period / self.emission_per_period.sum()
diff --git a/setup.py b/setup.py
index 89d5101..f601287 100644
--- a/setup.py
+++ b/setup.py
@@ -18,7 +18,7 @@
         'Programming Language :: Python :: 2.7',
         'Programming Language :: Python :: 3.4'
       ],
-      keywords='EZ-climate, social cost of carbon, SCC, climate pricing',
+      keywords='EZ-climate, optimal carbon price, CO2 tax, social cost of carbon, SCC, climate pricing',
       url='http://github.com/Litterman/EZClimate',
       author='Robert Litterman, Kent Daniel, Gernot Wagner',
       license='MIT',