Once the ball starts rolling, these are people who should be contacted.

Basically anything under educational charitable organization counts.

It is also worth having a look under the Wikipedia page for open educational resources: en.wikipedia.org/wiki/Open_educational_resources

The HNN extension, named after the mathematicians Graham Higman, B. H. Neumann, and Hanna Neumann, is a construction in group theory that allows the creation of new groups from existing ones. Specifically, an HNN extension is a type of group that is used to generalize the notion of groups with an additional structure, particularly when it comes to accommodating certain types of relations between groups.

Improve article editing which is very buggy and inconvenient!

I'll also look into some more likely easy but very important topic improvements:

From episode "Mortynight Run"

Funding:

This section discusses the pre-photon understanding of the polarization of light. For the photon one see: photon polarization.

polarization.com/history/history.html is a good page.

People were a bit confused when experiments started to show that light might be polarized. How could a wave that propages through a 3D homgenous material like luminiferous aether have polarization?? Light would presumably be understood to be analogous to a sound wave in 3D medium, which cannot have polarization. This was before Maxwell's equations, in the early 19th century, so there was no way to know.

Bdellium is a gum resin that is obtained from certain trees in the genus Commiphora, which are part of the Burseraceae family. The term "bdellium" is sometimes used to refer to a resin similar to myrrh. Historically, bdellium has been mentioned in ancient texts, including the Bible, where it is described as a valuable substance. The resin has been used for various purposes, including as an ingredient in perfumes, incense, and traditional medicine.

Lecture notes found by Googling "quantum field theory pdf":

Dirac field.

This book really tries to recall basic things to ensure that the reader will be able to understand the more advanced ones.

Sometimes it goes a little bit overboard, like defining what a function does several times.

But Ciro Santilli really prefers it when authors error on the side of obvious.