diff -r 9cd9f1c27fdd trytond/trytond/modules/account_invoice/invoice.xml
--- a/trytond/trytond/modules/account_invoice/invoice.xml	Mon Apr 23 17:32:58 2018 +0200
+++ b/trytond/trytond/modules/account_invoice/invoice.xml	Fri May 11 13:11:48 2018 +0200
@@ -132,6 +132,17 @@
         <menuitem parent="menu_invoices" action="act_invoice_in_form"
             id="menu_invoice_in_form" sequence="3"/>

+        <record model="ir.action.act_window" id="act_credit_notes_form">
+            <field name="name">Credit Notes</field>
+            <field name="res_model">account.invoice</field>
+            <field name="domain" eval="[('lines.origin.invoice', 'in', Eval('active_ids'), 'account.invoice.line')]" pyson="1"/>
+        </record>
+        <record model="ir.action.keyword" id="act_open_credit_notes_keyword1">
+            <field name="keyword">form_relate</field>
+            <field name="model">account.invoice,-1</field>
+            <field name="action" ref="act_credit_notes_form"/>
+        </record>
+
         <record model="ir.model.access" id="access_invoice">
             <field name="model" search="[('model', '=', 'account.invoice')]"/>
             <field name="perm_read" eval="False"/>
diff -r 9cd9f1c27fdd trytond/trytond/modules/account_invoice/locale/ca.po
--- a/trytond/trytond/modules/account_invoice/locale/ca.po	Mon Apr 23 17:32:58 2018 +0200
+++ b/trytond/trytond/modules/account_invoice/locale/ca.po	Fri May 11 13:11:48 2018 +0200
@@ -1127,6 +1127,10 @@
 msgid "Invoice Tax"
 msgstr "Impost de factura"

+msgctxt "model:ir.action,name:act_credit_notes_form"
+msgid "Credit Notes"
+msgstr "Abonaments"
+
 msgctxt "model:ir.action,name:act_invoice_form"
 msgid "Invoices"
 msgstr "Factures"
diff -r 9cd9f1c27fdd trytond/trytond/modules/account_invoice/locale/es.po
--- a/trytond/trytond/modules/account_invoice/locale/es.po	Mon Apr 23 17:32:58 2018 +0200
+++ b/trytond/trytond/modules/account_invoice/locale/es.po	Fri May 11 13:11:48 2018 +0200
@@ -1123,6 +1123,10 @@
 msgid "Invoice Tax"
 msgstr "Impuesto de factura"

+msgctxt "model:ir.action,name:act_credit_notes_form"
+msgid "Credit Notes"
+msgstr "Abonos"
+
 msgctxt "model:ir.action,name:act_invoice_form"
 msgid "Invoices"
 msgstr "Facturas"