To me, line 907 indicates that declared sets are considered referenced but that does not mean the converse is true (i.e., a thing referenced is not necessarily declared).   Are you using the ead dtd or ead schema or something else?  Even with a blank xml document with no schema or dtd declared I still can use & &lt, etc in oXygen 13.2 but I can replicate your issue with &hearts, &diams, &spades, etc. 

Entities have to be declared some place.

&hearts et al are declared in the Publishing extensions of ISO 8879 (see  

To declare the Publishing extensions, I added the following to my document :
<!DOCTYPE doc [
<!ENTITY % iso-pub PUBLIC "ISO 8879:1986//ENTITIES Publishing//EN//XML"

I put it after the <?xml ...> tag and before <ead> (Entities have to be declared in dtd since there is no support for them in xsd - see

Also if you have declared a schema in your xml document, in oXygen, click on Options|Preferences|XML|XML Parser and make sure the XML Parser Property "Ignore the DTD for validation if a schema is specified" is *not* checked.

Why you can't use &amp is a mystery, though.  Sorry.

Maury Bouchard
Simmons GSLIS

From: Elizabeth H Dow <[log in to unmask]>
To: [log in to unmask]
Sent: Tuesday, January 31, 2012 3:07 PM
Subject: The entity "hearts" was referenced, but not declared

The entity "hearts" was referenced, but not declared
I've run into an issue with oXygen 13.2 that baffles me.

I'm putting together a demonstration of how entities work for a class. I tried to create the note "I &hearts; Ben &amp; Jerry's ice cream" to make my point.

I got the following error message: "The entity "hearts" was referenced, but not declared" and the file does not parse.

I found the following statement at line 907 of the DTD "By default, all declared sets are referenced" which leads me to believe that I do not need to declare the standard ISO entities individually.

Can anyone offer any insight as to why I've hit this problem. FYI, I got the same message for &amp; .

Elizabeth H. Dow
School of Library and Information Science
Louisiana State University