Name authorities:
https://www.loc.gov/cds/products/MDSConnect-name_authorities.html
https://www.loc.gov/item/2020445556/

Subjects:
https://www.loc.gov/item/2020445559/

Serials
https://doaj.org/docs/public-data-dump/

Other LOC materials

https://www.loc.gov/cds/

classifications:
https://www.loc.gov/item/2020445551/

https://www.loc.gov/aba/publications/FreeLCC/LCC_PL-PM2022OUT.pdf