Publication layout: preferred syntax for printed dois is with doi: prefix

_layouts/publication.html

@@ -14,7 +14,7 @@ menu: false
         <p class="card-text">{{ page.entry.keywords }}</p>{% endif %}
         {% if page.entry.doi or page.entry.isbn %}<h5 class="card-title">Identifiers</h5>
         <ul class="site-card-list">
-          {% if page.entry.doi %}<li>DOI: <a href="http://dx.doi.org/{{ page.entry.doi }}">{{ page.entry.doi }}</a></li>{% endif %}
+          {% if page.entry.doi %}<li>DOI: <a href="http://dx.doi.org/{{ page.entry.doi }}">doi:{{ page.entry.doi }}</a></li>{% endif %}
           {% if page.entry.isbn %}<li>ISBN: {{ page.entry.isbn }}</li>{% endif %}
         </ul>{% endif %}
       </div>