Update readme with usefull links

Author: dodogabrie

README.md

@@ -3,6 +3,10 @@ Evaluate the Lyapunov Spectrum of a dynamical system described by ODEs
 
 [Documentation](https://evales.readthedocs.io/en/latest/?badge=latest.)
 
+[Example of Usage](https://nbviewer.jupyter.org/github/dodogabrie/evaLEs/blob/main/HowToUse.ipynb)
+
+Article of [Sandri](https://www.researchgate.net/publication/240477720_Numerical_calculation_of_Lyapunov_exponents) about the algorithm of Benedettin et al.
+
 # How to install:
 ```
 pip install evaLEs