diff --git a/requirements.txt b/requirements.txt
index 202af33..19264a7 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,14 +1,14 @@
-docopt
-matplotlib
-mkdocs
-mkdocs-cinder
-networkx
-numpy
-p_tqdm
-pandas
-pyomo
-pytest
-python-markdown-math
-seaborn
-sklearn
-tqdm
+docopt~=0.6
+matplotlib~=3.3
+mkdocs~=1.1
+mkdocs-cinder~=1.2
+networkx~=2.5
+numpy~=1.19
+p_tqdm~=1.3
+pandas~=1.1
+pyomo~=5.7
+pytest~=6.1
+python-markdown-math~=0.8
+seaborn~=0.11
+scikit-learn~=0.23
+tqdm~=4.54