diff --git a/inbox/automatic-trust-transfer.xml b/inbox/automatic-trust-transfer.xml
index b0ce34f3..c715faa5 100644
--- a/inbox/automatic-trust-transfer.xml
+++ b/inbox/automatic-trust-transfer.xml
@@ -120,8 +120,20 @@
OMEMO message which indicates that specific keys can be trusted (authentication) or no longer trusted (revocation).
A trust message for a device's key sent to another device is a trust message that contains the key identifer of the given key for authentication or revocation.
- If a trust message only contains key identifiers for authentication, it is called authentication message.
- If it only contains key identifiers for revocation, it is called revocation message.
+
+
+
+ Authentication message
+
+ Trust message which only contains key identifiers for authentication.
+ If a trust message contains authentication and revocation parts, the term authentication message is used for referring to the trust message without revocation parts.
+
+
+
+ Revocation message
+
+ Trust message which only contains key identifiers for revocation.
+ If a trust message contains authentication and revocation parts, the term revocation message is used for referring to the trust message without authentication parts.