<?xml version="1.0" encoding="utf-8"?><mads xmlns="http://www.loc.gov/mads/" xmlns:mods="http://www.loc.gov/mods/v3" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.loc.gov/mads/
mads.xsd"><authority><topic authority="http://AATesaurus.cultura.gencat.cat/aat/getty_en">invariant nouns</topic></authority><related type="broader"><topic>nouns</topic></related><variant type="other"><topic>invariable nouns</topic></variant><variant type="other"><topic>invariant noun</topic></variant> <note xml:lang="en"><![CDATA[ Nouns that do not change form between singular and plural. For example, in English "aircraft" may refer to one or to multiple vehicles. ]]></note></mads>