diff --git a/cps/templates/detail.html b/cps/templates/detail.html
index 510cfb68..ce7e179a 100644
--- a/cps/templates/detail.html
+++ b/cps/templates/detail.html
@@ -126,7 +126,7 @@
               </button>
               <ul class="dropdown-menu" aria-labelledby="btnGroupDrop1">
                 {% for format in entry.data %}
-                <li><a href="{{ url_for('get_download_link_ext', book_id=entry.id, format=format.format|lower, anyname=entry.title+'.'+format.format) }}">{{format.format}}</a></li>
+                <li><a href="{{ url_for('get_download_link_ext', book_id=entry.id, format=format.format|lower, anyname=entry.id|string+'.'+format.format) }}">{{format.format}}</a></li>
                 {%endfor%}
               </ul>
             </div>