diff --git a/frontend/images/icon_unknown.png b/frontend/images/icon_unknown.png
new file mode 100644
index 0000000..c4c2508
Binary files /dev/null and b/frontend/images/icon_unknown.png differ
diff --git a/graphics/questionmark.svg b/graphics/questionmark.svg
new file mode 100644
index 0000000..e3add52
--- /dev/null
+++ b/graphics/questionmark.svg
@@ -0,0 +1,71 @@
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+
+<svg
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+   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"
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+   height="16"
+   id="svg2"
+   version="1.1"
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+     bordercolor="#666666"
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+     inkscape:document-units="px"
+     inkscape:current-layer="layer1"
+     showgrid="false"
+     showguides="true"
+     inkscape:guide-bbox="true"
+     inkscape:window-width="1366"
+     inkscape:window-height="713"
+     inkscape:window-x="0"
+     inkscape:window-y="0"
+     inkscape:window-maximized="1" />
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+     id="metadata7">
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+         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>
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+     inkscape:groupmode="layer"
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