At its core, it’s a content-focused strategy for any link building campaign. You simply find dead (or broken) links, analyze the page for relevance and create more valuable content to replace the broken content. This helps site owners, editors and webmasters improve their site user experience by replacing broken links with a link to your page based on a search term.
https://scholar.google.com.gt/citations?user=1wNFD-QAAAAJ&hl=en&authuser=8