Idk if you’re asking about specifically anarchist reading here, if not:

• Principles of Communism by Engels is a good essay-length read ( https://www.marxists.org/archive/marx/works/1847/11/prin-com.htm ).

• State and Revolution by Lenin is a great first short book length read ( https://www.marxists.org/archive/lenin/works/1917/staterev/ ).

• On Authority is Engel’s argument essay against Anarchism and the term “Authoritarian” . That may or may not be up your alley, but you’ll see a lot of that reflected in what we say here ( https://www.marxists.org/archive/marx/works/1872/10/authority.htm ).

• And just because Mao is rad, “Oppose Book Worship” includes the banger “no investigation, no right to speak” and I like that. ( https://www.marxists.org/reference/archive/mao/selected-works/volume-6/mswv6_11.htm#fn5 ).

If you’re looking for Anarchist theory you could try an Anarchist instance. I think they like Bookchin or something like that.