diff --git a/Doc/lectures.xml b/Doc/lectures.xml
index 150dd25f36ff07b911695edab674b60cda3ac87a..23f2f22faefe12eb3403335419b5ef92150c8af2 100644
--- a/Doc/lectures.xml
+++ b/Doc/lectures.xml
@@ -81,19 +81,37 @@
       <listitem xml:id="prefaceFormatEpub">
         <para><filename
         xlink:href="https://freedocs.mi.hdm-stuttgart.de/webhelp/lectures.epub">lectures.epub</filename>
-        featuring the <xref linkend="glo_EPUB"/> format containing <xref
+        featuring the <xref linkend="glo_EPUB"/> 3 format containing <xref
         linkend="glo_SVG"/> images and MathML formulas based on <link
         xlink:href="https://www.mathjax.org">MathJax JavaScript</link>
         rendering.</para>
 
         <caution>
-          <para>Since <productname
+          <para><productname
           xlink:href="https://en.wikipedia.org/wiki/EPUB">Epub</productname>
-          readers do not (yet) support <xref linkend="glo_EPUB"/> 3.0 both
-          formulas and <xref linkend="glo_SVG"/> images have been converted to
-          <xref linkend="glo_PNG"/> files. This may account for poor image
-          quality.</para>
+          reader applications do vary supporting <xref linkend="glo_EPUB"/>
+          3.0 (e.g. formulas and <xref linkend="glo_SVG"/> images). Reader
+          apps known to work well:</para>
         </caution>
+
+        <para>Reader apps known to work well:</para>
+
+        <itemizedlist>
+          <listitem>
+            <para><link xlink:href="http://gitden.com">Gitden
+            reader</link></para>
+          </listitem>
+
+          <listitem>
+            <para><link
+            xlink:href="https://www.calibre-ebook.com">Calibre</link></para>
+          </listitem>
+
+          <listitem>
+            <para>The author very much welcomes hints to appropriate software
+            accessing these pages.</para>
+          </listitem>
+        </itemizedlist>
       </listitem>
 
       <listitem xml:id="prefaceFormatPdf">