app/views/content/panels/_documents.html.erb
<%
visible_documents = content.documents.includes(:user).select { |document| (current_user || User.new).can_read?(document) }
%>
<div id="documents_panel" class="panel">
<%= render partial: 'notice_dismissal/messages/10' %>
<% if visible_documents.any? %>
<div class="grey-text uppercase center">
<%= content.name %> appears in the following documents
</div>
<% visible_documents.each do |document| %>
<%= link_to document do %>
<div class="card-panel hoverable <%= Document.color %> lighten-5">
<%= render partial: 'documents/reference_card', locals: { document: document } %>
</div>
<% end %>
<% end %>
<% end %>
</div>