Algebraic topology
https://en.wikipedia.org/wiki/Algebraic_topologyLes groupes d'homotopie - Science4All
Groupe fondamental
https://fr.wikipedia.org/wiki/Groupe_fondamentalSimplicial complex
https://en.wikipedia.org/wiki/Simplicial_complexEuler characteristic
https://en.wikipedia.org/wiki/Euler_characteristicLefschetz fixed-point theorem
https://en.wikipedia.org/wiki/Lefschetz_fixed-point_theoremTopological combinatorics
https://en.wikipedia.org/wiki/Topological_combinatoricsTopologie : Revêtements et Groupe Fondamental - Michèle Audin
http://irma.math.unistra.fr/~maudin/courstopalg.pdf