Prresentation with speech used in the webinar "An introduction to railway power systems", organized by the IEEE Transportation Electrification Community (26 Oct 2016)
https://www.youtube.com/watch?v=mzDbQhH6OR4&list=PLenRU1-KeAr-mo3B8K0_UU8eu_X0qEFuJ&pbjreload=101