diff --git a/imgsrc/reference.svg b/imgsrc/reference.svg
new file mode 100644
index 0000000000..4b6b1bd715
--- /dev/null
+++ b/imgsrc/reference.svg
@@ -0,0 +1,63 @@
+<?xml version="1.0" encoding="UTF-8" standalone="no"?>
+<!-- Created with Inkscape (http://www.inkscape.org/) -->
+
+<svg
+   xmlns:dc="http://purl.org/dc/elements/1.1/"
+   xmlns:cc="http://creativecommons.org/ns#"
+   xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
+   xmlns:svg="http://www.w3.org/2000/svg"
+   xmlns="http://www.w3.org/2000/svg"
+   xmlns:sodipodi="http://sodipodi.sourceforge.net/DTD/sodipodi-0.dtd"
+   xmlns:inkscape="http://www.inkscape.org/namespaces/inkscape"
+   width="128"
+   height="128"
+   viewBox="0 0 33.866666 33.866668"
+   version="1.1"
+   id="svg840"
+   inkscape:version="0.92.4 5da689c313, 2019-01-14"
+   sodipodi:docname="reference.svg">
+  <defs
+     id="defs834" />
+  <sodipodi:namedview
+     id="base"
+     pagecolor="#ffffff"
+     bordercolor="#666666"
+     borderopacity="1.0"
+     inkscape:pageopacity="0.0"
+     inkscape:pageshadow="2"
+     inkscape:zoom="0.98994949"
+     inkscape:cx="237.114"
+     inkscape:cy="236.75119"
+     inkscape:document-units="mm"
+     inkscape:current-layer="layer1"
+     showgrid="false"
+     units="px"
+     inkscape:window-width="2560"
+     inkscape:window-height="1400"
+     inkscape:window-x="0"
+     inkscape:window-y="40"
+     inkscape:window-maximized="0" />
+  <metadata
+     id="metadata837">
+    <rdf:RDF>
+      <cc:Work
+         rdf:about="">
+        <dc:format>image/svg+xml</dc:format>
+        <dc:type
+           rdf:resource="http://purl.org/dc/dcmitype/StillImage" />
+        <dc:title></dc:title>
+      </cc:Work>
+    </rdf:RDF>
+  </metadata>
+  <g
+     inkscape:label="Layer 1"
+     inkscape:groupmode="layer"
+     id="layer1"
+     transform="translate(0,-263.13332)">
+    <path
+       inkscape:connector-curvature="0"
+       d="M 8.7798497,295.71845 H 1.3855535 v -20.36721 l 9.0289685,-10.48359 a 1.5135715,1.4801752 0 0 1 2.655827,0.73022 v 0 a 7.2651433,7.104841 0 0 1 -1.190691,5.10365 l -2.8253283,3.9866 20.7379663,0.46971 a 2.7647919,2.7037879 0 1 1 0,5.40757 l -12.157027,0.71443 -1.743642,8.71133 a 7.2651433,7.104841 0 0 1 -7.1117773,5.72729 z"
+       id="path4147"
+       style="fill:#116def;fill-opacity:1;stroke-width:0.31270596" />
+  </g>
+</svg>
diff --git a/resources/images/reference.png b/resources/images/reference.png
new file mode 100644
index 0000000000..de203aa003
Binary files /dev/null and b/resources/images/reference.png differ
diff --git a/src/calibre/gui2/viewer/toolbars.py b/src/calibre/gui2/viewer/toolbars.py
index 6f029e3e2a..2fc11dc6ed 100644
--- a/src/calibre/gui2/viewer/toolbars.py
+++ b/src/calibre/gui2/viewer/toolbars.py
@@ -50,7 +50,7 @@ def all_actions():
             'previous': Action('previous.png', _('Previous page'), 'previous'),
             'toc': Action('toc.png', _('Table of Contents'), 'toggle_toc'),
             'bookmarks': Action('bookmarks.png', _('Bookmarks'), 'toggle_bookmarks'),
-            'reference': Action('lookfeel.png', _('Toggle Reference mode'), 'toggle_reference_mode'),
+            'reference': Action('reference.png', _('Toggle Reference mode'), 'toggle_reference_mode'),
             'lookup': Action('generic-library.png', _('Lookup words'), 'toggle_lookup'),
             'chrome': Action('tweaks.png', _('Show viewer controls'), 'show_chrome'),
             'mode': Action('scroll.png', _('Toggle paged mode'), 'toggle_paged_mode'),
diff --git a/src/pyj/read_book/overlay.pyj b/src/pyj/read_book/overlay.pyj
index e62e955240..1e179e23cd 100644
--- a/src/pyj/read_book/overlay.pyj
+++ b/src/pyj/read_book/overlay.pyj
@@ -259,6 +259,7 @@ class MainOverlay:  # {{{
 
         if runtime.is_standalone_viewer:
             toc_actions.appendChild(bookmarks_action)
+        toc_actions.appendChild(ac(_('Reference mode'), _('Toggle the Reference mode'), self.overlay.toggle_reference_mode, '🖝', True))
 
         actions_div = E.div( # actions
             nav_actions,
@@ -607,6 +608,10 @@ class Overlay:
         self.panels.push(TOCOverlay(self))
         self.show_current_panel()
 
+    def toggle_reference_mode(self):
+        self.hide_current_panel()
+        self.view.toggle_reference_mode()
+
     def show_bookmarks(self):
         self.hide_current_panel()
         if runtime.is_standalone_viewer: