Country name used within an address.
<!ELEMENT country (#PCDATA %country-elements;)* >
(#PCDATA | x)*
Any combination of:
<address>, <addr-line>, <aff>, <collab>, <corresp>, <publisher-loc>
...
<contrib contrib-type="author" id="a4762">
<name><surname>Knutson</surname>
<given-names>Doug</given-names></name>
<degrees>MD</degrees>
<aff rid="a4762">
<institution>The Ohio State University</institution>
<addr-line>Columbus, Ohio</addr-line>
</aff>
<address>
<institution>The Ohio State University, Department
of Family Medicine</institution>
<addr-line>2231 N. High St.</addr-line>
<addr-line>Columbus, OH 43201</addr-line>
<country country="US">United States</country>
<email>doug.knutson@osumc.edu</email>
</address>
...
</contrib>
...