others
This exposition at Freie universität is very cool
This seminar is really cool: TDCM.
This seminar is really cool: 3-Manifolds Berlin.
Poincaré's homology sphere, taken from W. Threlfall and H. Seifert 's classic "Topologische Untersuchung der Diskontinuitätsbereiche endlicher Bewegungsgruppen des dreidimensionalen sphärischen Raumes".
This seminar is really cool: Conjunto no vacio.