diff --git a/README.md b/README.md
index 704be89aec1b973c526ee8ca661a078e1b710983..2ecda0ff1b2259b9fb4ea8ed79a4cb62bc1cfbd4 100644
--- a/README.md
+++ b/README.md
@@ -169,7 +169,7 @@ It can be conveniently run by executing `pytest` in the `tests/` folder:
 ## Requirements
 python\_dicthash ([https://github.com/INM-6/python-dicthash](https://github.com/INM-6/python-dicthash)),
 correlation\_toolbox ([https://github.com/INM-6/correlation-toolbox](https://github.com/INM-6/correlation-toolbox)),
-pandas, numpy, nested_dict, matplotlib (2.1.2), pyx, scipy, NEST 2.14.0
+pandas, numpy, nested_dict, matplotlib (2.1.2), scipy, NEST 2.14.0
 
 Optional: seaborn, Sumatra
 
@@ -179,7 +179,7 @@ To install the required packages in a conda environment, execute:
 
 Note that NEST needs to be installed separately, see <http://www.nest-simulator.org/installation/>.
 
-In addition, reproducing the figures of [1] requires python-igraph and networkx. To install these additional packages, execute:
+In addition, reproducing the figures of [1] requires networkx, python-igraph and pyx. To install these additional packages, execute:
 
 `pip install -r figures/Schmidt2017/additional_requirements.txt`
 
diff --git a/environment.yaml b/environment.yaml
index 46ef9cfbc3ea0a199b6750cf257dedc73dff6305..08b55feb9b9663397e3bcf9bddf5729c3bb133de 100644
--- a/environment.yaml
+++ b/environment.yaml
@@ -8,5 +8,3 @@ dependencies:
  - pip:
    - nested_dict
    - https://github.com/INM-6/python-dicthash/archive/master.zip
-   - pyx
-  
diff --git a/figures/Schmidt2017/additional_requirements.txt b/figures/Schmidt2017/additional_requirements.txt
index d60715850a454f9bd0f746c1ae3e834cb8284731..59d44333521bc4985813c8eaf044ea231a970ef4 100644
--- a/figures/Schmidt2017/additional_requirements.txt
+++ b/figures/Schmidt2017/additional_requirements.txt
@@ -1,2 +1,3 @@
 python-igraph
 networkx
+pyx