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In my opinion, the presented factual information in this post qualifies as common knowledge. The shared information can be found in a large number of sources and can be considered as non-controversial. Therefore, no obligation to add references. Having said that, to decide whether a given piece of information is common knowledge or not can be a matter of perspective.

Perspective exactly! For someone new into this further studying is needed. That's why we are for active links, so that anyone interested can check out for themselves ;)