While I have always preferred physical books to digital, I have made use of several online sources of occult works for reference, especially when discussing topics online. With a focus on Uncle Al, one source in particular has been a favorite over the years for their approach to the integrity of his work. Through donations, they procure and carefully scan original editions of Aleister Crowley's Libri and provide them in both low and high quality PDF downloads. Furthermore, using an excellent method you can also sort them by title, Class and intended audience.

Scans from the Equinox:
https://keepsilence.org/the-equinox/

Note: As any reader of Uncle Al's knows there were many typos and misprints in the early self-published, and sometimes publisher-released first editions. Many websites I used to follow had well-outlined comparisons between editions of his work, but sadly none that I was familiar with are still around. I find Keep Silence holds value for their preservation of the unfettered word but serious students should also keep current and well-commented editions for their practice.

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