[[https://cecs.wright.edu/~sthomas/htchapter02.pdf|https://cecs.wright.edu/~sthomas/htchapter02.pdf]]
[[https://www.math.colostate.edu/~bangerth/videos.html|https://www.math.colostate.edu/~bangerth/videos.html]]
[[https://www.osti.gov/servlets/purl/986602-ENHb2G/|https://www.osti.gov/servlets/purl/986602-ENHb2G/]]
[[https://www.osti.gov/servlets/purl/1724498|https://www.osti.gov/servlets/purl/1724498]]
[[https://www.youtube.com/watch?v=FuKThdBYIX4|https://www.youtube.com/watch?v=FuKThdBYIX4]]

[[https://onlinelibrary.wiley.com/doi/epdf/10.1002/cnm.1063|https://onlinelibrary.wiley.com/doi/epdf/10.1002/cnm.1063]]