gistfile1.txt

% curl -s https://www.loc.gov/ | grep 'name=\"dc\.\|property=\"og:'
<meta name="dc.identifier"
<meta name="dc.language" content="eng" />
<meta name="dc.source" content="Library of Congress, Washington, D.C. 20540 USA" />
<meta property="og:site_name" content="The Library of Congress"/>
<meta property="og:type" content="article" />
    <meta name="dc.title"
    <meta property="og:title"
        <meta property="og:description" content="The world's largest library. View historic 
        photos, maps, books and more. Contact experts for help with research. Plan a visit. 
        Home of U.S. Copyright Office." />
    <meta name="dc.rights" content="Text is U.S. Government Work" />
<meta property="og:image" content='http://www.loc.gov/static/images/favicons/open-graph-logo.png' />
<meta property="og:image:secure_url" 
  content='https://www.loc.gov/static/images/favicons/open-graph-logo.png' />
<meta property="og:image:width" content="1200"/>
<meta property="og:image:height" content="630"/>