HTTP/3 explained, https://daniel.haxx.se/http3-explained/
A great book by @bagder about HTTP/3.
Of course, it is open source, https://github.com/bagder/http3-explained
A must read :-). I highly recommend it. It's well-written and quick to apprehend.
Formats: Web, PDF, Mobi, and ePub. No paper.
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