<?xml version="1.0" encoding="utf-8"?><!DOCTYPE Zthes SYSTEM "http://zthes.z3950.org/xml/zthes-05.dtd">  <Zthes><term><termId>31328523</termId><termName>twenty-first century BCE</termName><termType>PT</termType><termNote><![CDATA[ Century in the proleptic Gregorian calendar including the years 2099 to 2000 (or 2100 to 2001) Before Common Era. ]]></termNote><termCreatedDate>2026-03-30 20:28:33</termCreatedDate><relation><relationType>UF</relationType><termId>31328524</termId><termName>21st century B.C.</termName><termType>ND</termType></relation><relation><relationType>UF</relationType><termId>31328525</termId><termName>21st century BCE</termName><termType>ND</termType></relation><relation><relationType>UF</relationType><termId>31328526</termId><termName>21st-century BCE</termName><termType>ND</termType></relation><relation><relationType>UF</relationType><termId>31328527</termId><termName>century, twenty-first, BCE</termName><termType>ND</termType></relation><relation><relationType>BT</relationType><termId>31309694</termId><termName>dates by century or millennium</termName><termType>PT</termType></relation></term>  </Zthes>