Humblebundle:

https://www.humblebundle.com/books/unix-linux-books

https://www.humblebundle.com/books/machine-learning-bookshelf-no-starch-press-books

https://twitter.com/aionescu/status/1432731234728304641

https://www.microsoftpressstore.com/store/windows-internals-part-2-9780135462409

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