title: convert Vector to a single but atypical string in R
body: <p>I have a Question. I would like to convert my vector:</p>
  
  <pre><code>x &lt;- c("9781405287623", "9780762100019", "9780007949977", "9780670509386")
  </code></pre>
  
  <p>To get one string:</p>
  
  <pre><code>"9781405287623","9780762100019","9780007949977","9780670509386"
  </code></pre>
  
  <p>to be understood well. I want quotation mark to start and close IDs that will be separated by commas. And this has to be one string. Any ideas how to do that?</p>