diff --git a/epub33/core/index.html b/epub33/core/index.html index 7a2692603..1cf7f2e3c 100644 --- a/epub33/core/index.html +++ b/epub33/core/index.html @@ -3179,10 +3179,9 @@
The itemref Element
-

Each itemref element MUST reference the ID - [[XML]] of a unique item in the - manifest via the IDREF [[XML]] in its idref attribute (i.e., two - or more itemref elements cannot reference the same item).

+

Each itemref element MUST reference the ID of an item in the manifest via the IDREF [[XML]] + in its idref attribute, and item IDs MUST NOT be referenced more than once. +

Each referenced manifest item MUST be either a) an EPUB Content Document or b) another type of Publication Resource which, diff --git a/epub33/rs/index.html b/epub33/rs/index.html index 138f65503..22fa5a237 100644 --- a/epub33/rs/index.html +++ b/epub33/rs/index.html @@ -551,6 +551,19 @@

Spine

Reading Systems MUST ignore all values expressed in spine itemref properties attributes that they do not recognize.

+ +

+ Reading Systems MUST NOT skip spine references to duplicate manifest items when rendering the linear reading order. + + The Reading System MUST treat these as distinct items for UI purposes (for example, each occurrence + could be independently bookmarked or annotated). + + + When a Reading System follows a hyperlink to a resource referenced multiple times in the + spine, the Reading System MUST move to the position of the first occurrence of the + document in the linear reading order. + +

@@ -2238,6 +2251,10 @@

Change Log

>Working Group's issue tracker.