Add an Attribution Line to Feed Items
Appends "The post ... first appeared on ..." with links to every feed item, which credits you when content is scraped from your feed.
Snippet Library
RSS Feeds snippets for WordPress
Snippets for WordPress RSS feeds: add featured images and custom post types, delay publishing to feeds, credit your site on scraped content or turn feeds off. For publishers and podcasters whose readers follow along by feed or email.