This recent case discusses Adickes v. S. H. Kress and Company (U.S. 1970).
Richard H. McClure,
Civil Rights-State Action-Customs Having the Force of Law by Virtue of Persistent Practices of State Officials Constitute State Action. Adickes v. S. H. Kress and Company (U.S. 1970),
San Diego L. Rev.
Available at: https://digital.sandiego.edu/sdlr/vol8/iss1/16