What is Reddit's opinion of Symmetries and Curvature Structure in General Relativity (World Scientific Lecture Notes in Physics)?

From 3.5 billion Reddit comments

For a DIY approach, look at Universal Decimal Classification. It's used in just about every modern library around the world for content indexing of text, media, maps, realia, etc.

If you are forming an ark, or perhaps better an Encyclopedia Galactica, you could find digitized copies (or digitize them yourself) of the best textbooks in each field. Also include the relevant Wikipedia article if there is one. If you want to go even further, find video lectures on that specific topic and digital copies of the most cited research papers on that subject.

So for UDC 539.120.226 Spacetime symmetries you would catalog:

• Spacetime symmetries | wikipedia
  
• obtain a digital copy of Symmetries and Curvature Structure in General Relativity or use this
  
• maybe download Noether's Theorem and The Symmetries of Reality |PBS Space Time Youtube

This whole process will be painstaking and take a lot of domain-specific knowledge.