“Schema Theory” Wikipedia page: see Brewer & Treyens (1981) in the article
Brewer & Treyens (1981): here’s the abstract to their original study. You also have the option of paying to download the entire article. Be sure to read the “related articles” and “related reference work articles” boxes on the right hand side. You’ll find other helpful sources here. IF THE LINK DOESN’T WORK: go to Google Scholar & search for “Brewer Treyens”. It’s the first result.
Brewer & Treyens (1981): in a paragraph towards the end of the page