title: Hyperlink in R document
body: <p>I am writing an R document (Rd) for functions. In markdown, we can create a hyperlink by <code>[google](https://www.google.com)</code>. How can I replicate this in R document?</p>
  
  <p>It seems that <code>\link{...}</code> can only create a link, which is different from what I am looking for.</p>