diff --git a/README.rst b/README.rst
index 640a5bf..8619650 100644
--- a/README.rst
+++ b/README.rst
@@ -20,10 +20,12 @@ Continuum Mechanics
 .. image:: https://mybinder.org/badge_logo.svg
     :target: https://mybinder.org/v2/gh/nicoguaro/continuum_mechanics/master
 
-
 .. image:: https://img.shields.io/pypi/dm/continuum_mechanics
     :target: https://pypistats.org/packages/continuum-mechanics
 
+.. image:: https://zenodo.org/badge/130519974.svg
+   :target: https://zenodo.org/badge/latestdoi/130519974
+
 Utilities for doing calculations in continuum mechanics.
 
 
@@ -38,6 +40,33 @@ Features
 * Support different coordinate systems.
 * Visualize entities such as second rank tensors.
 
+
+Citation
+--------
+
+To cite `continuum_mechanics` in publications use
+
+    Nicolás Guarín-Zapata. (2020). nicoguaro/continuum_mechanics: Version 0.2.1
+    (Version v0.2.1). Zenodo. http://doi.org/10.5281/zenodo.4029448
+
+A BibTeX entry for LaTeX users is
+
+.. code:: bibtex
+
+    @software{continuum_mechanics,
+     title = {continuum_mechanics: Continuum Mechanics calculations in Python},
+     version = {0.2.1},
+     author = {Guarín-Zapata, Nicolás},
+     year = 2020,
+     keywords = {Python, Finite elements, Scientific computing, Computational mechanics},
+     abstract = {`continuum_mechanics` is a Python package built on top of SymPy to aid
+        with calculations in Continuum Mechanics that are commonly lengthy and
+        tedious if done by hand. It also provides visualization capabilities for
+        second-order tensors such as Mohr's circle to help in stress analyses.},
+     url = {https://github.com/nicoguaro/continuum_mechanics},
+     doi = {http://doi.org/10.5281/zenodo.4029448}
+    }
+
 Credits
 -------
 
diff --git a/requirements.txt b/requirements.txt
index 0d850f6..3fcd012 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,5 +1,4 @@
 sympy>=1.3
 matplotlib>=3
-numpy==1.19.0
-scipy==1.5.1
-
+numpy==1.20.2
+scipy==1.6.2
diff --git a/requirements_dev.txt b/requirements_dev.txt
index c4dfe38..68cbe6f 100644
--- a/requirements_dev.txt
+++ b/requirements_dev.txt
@@ -1,12 +1,12 @@
 -r requirements.txt
-pip==20.1.1
+pip==21.0.1
 bumpversion==0.6.0
-wheel==0.34.2
-watchdog==0.10.3
-flake8==3.8.3
-tox==3.16.1
-coverage==5.2
-Sphinx==3.1.2
-twine==3.2.0
-pytest==5.4.3
-pytest-runner==5.2
+wheel==0.36.2
+watchdog==2.0.2
+flake8==3.9.0
+tox==3.23.0
+coverage==5.5
+Sphinx==3.5.4
+twine==3.4.1
+pytest==6.2.3
+pytest-runner==5.3.0
\ No newline at end of file