https://nptel.ac.in/
https://www.dierk-raabe.com/
http://pajarito.materials.cmu.edu/27750/27750.html
http://solidmechanics.org/index.html
https://www.doitpoms.ac.uk/tlplib/work_harden/index.php
https://www.feynmanlectures.caltech.edu/
https://www.ioc.ee/~kalda/ipho/