--- a/RelaxNG/publidoc.rnc	mar. sept. 18 12:35:17 2012 +0200
+++ b/RelaxNG/publidoc.rnc	ven. sept. 21 17:50:59 2012 +0200
@@ -319,7 +319,7 @@
    media.id.attribute
  & image.type?
 media.id.attribute = attribute id { xsd:NMTOKEN }
-image.type = attribute type { "thumbnail" | "icon" }
+image.type = attribute type { "cover" | "thumbnail" | "icon" }
 
 image.content =
    copyright?,