diff --git a/ui/NOTES.md b/ui/NOTES.md
index 15777c2..810989d 100644
--- a/ui/NOTES.md
+++ b/ui/NOTES.md
@@ -14,7 +14,7 @@ uuid[v5?] -[is part of]-> file hash, time stamp range [e.g. section of video fil
 Namespaces:
 
 These are shorthand:
-`dc:xxx` -> Dublin Core
+`dc:xxx` -> Dublin Core[DublinCore]
 `upnp:xxx` -> UPnP Content Directory Service
 `ms:xxx` -> medashare defined
 
@@ -28,15 +28,18 @@ old programs to handle new namespaces.
 
 
 Common dc properties:
-date
+date	(ISO-8601-1, https://www.dublincore.org/specifications/dublin-core/dcmi-terms/terms/date/)
 creator
 title
-format (see mime-type)
+format (not used, see mimetype)
 description
-extent (file size & duration)
+extent (file size, pixel dimentions & duration)
+		[1-9][0-9]*(T|G|M|K)?B		- file size
+		<regex for ISO 8601 duration>	- duration
+		[1-9][0-9]*x[1-9][0-9]*(@[1-9][0-9]*)?	- resolution in pixels w/ optional fps
 spatial (location)
 
-Common upnp properties:
+Common UPnP properties:
 artist
 actor
 actor@role -- XXX how to represent?
@@ -47,6 +50,22 @@ seriesTitle -- title of the TV series e.g. The West Wing
 programCode
 programCode@type	(matchingID from SRS, use domain_uniq, e.g. funkthat.com_generic when there isn't anything special about the programCode, funkthat.com_generic_tv when it matches the standard TV show, such as S02E05)
 
+Note, the actor@role is represented by the pair (actor, name of
+character).  That is, if there is the property "upnp:actor": "Actor Name",
+to represent that actor plays the roll "Roll Name", and aditional
+property/value pair would be added, "Actor Name": "Roll Name".
+
+In order to disambiguate actors, there may be an additional property
+that is "Actor Name": <urn>, where <urn> can be "urn:uuid:<uuid>" or
+another URI to uniquely identify the actor.  If there is not an
+additional property to disambiguate an actor, it must be assumed that
+they are different between two objects.  It is up to the client to
+manage this, such as propting if it matches a previously known actor,
+or if it should create a new one.  It is recommended that a random UUID
+is added, if unknown.  It can always be changed.  <make it mandatory to
+add the UUID?> <need an alias db a well w/ recommended value>.  <expand
+upon how equality works, e.g.  similar to SQL NULL>
+
 Common ms properties:
 tag
 private	-- will be ignored in general searches, unless explicitly added (value does not matter)
@@ -76,3 +95,5 @@ URN for hashes:
 https://www.nuke24.net/docs/2015/HashURNs.html
 https://github.com/hash-uri/hash-uri
 https://datatracker.ietf.org/doc/html/draft-thiemann-hash-urn-01
+
+[DublinCore]: https://www.dublincore.org/resources/userguide/creating_metadata/