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                <p>The three volumes of the Lord of the Rings novel are:
  <data value='0-345-24032-4'>The Fellowship of the Ring</data>,
  <data value='0-345-23510-X'>The Two Towers</data>, and
  <data value='0-345-24034-0'>The Return of the King</data>.</p>
<p><i>ISBNs of the books mentioned in this page:</i>
  <span id='ISBNListBlank'></span></p>




                const ISBNListBlank = document.querySelector('#ISBNListBlank')
const dataElements = document.querySelectorAll('data');
const ary = [];
dataElements.forEach((dataElements)=>ary.push(dataElements.textContent + ' : ' + dataElements.value));
ISBNListBlank.textContent = ary.join(', ');