Update 12.temporary_ins/10.electrostatics-vacuum/40.gauss-theorem-applications/10.gauss-integral-method/10.main/textbook.fr.md

Update 12.temporary_ins/10.electrostatics-vacuum/40.gauss-theorem-applications/05.gauss-symetries-invariances/10.main/textbook.fr.md

Update 12.temporary_ins/10.electrostatics-vacuum/40.gauss-theorem-applications/25.cylindrical-charge-distributions/20.gauss-local/20.overview/cheatsheet.fr.md

Update 12.temporary_ins/10.electrostatics-vacuum/40.gauss-theorem-applications/25.cylindrical-charge-distributions/10.gauss-integral/20.overview/cheatsheet.fr.md

Update 12.temporary_ins/05.coordinates-systems/40.spherical-coordinates/20.overview/cheatsheet.fr.md