<?xml version="1.0" encoding="utf-8"?><!DOCTYPE Zthes SYSTEM "http://zthes.z3950.org/xml/zthes-05.dtd">  <Zthes><term><termId>31439901</termId><termName>rigid structures</termName><termType>PT</termType><termNote><![CDATA[ Structures that do not undergo appreciable changes in shape under the actions of loads. ]]></termNote><termCreatedDate>2026-03-30 20:58:34</termCreatedDate><relation><relationType>UF</relationType><termId>31439902</termId><termName>rigid structure</termName><termType>ND</termType></relation><relation><relationType>UF</relationType><termId>31439903</termId><termName>structures, rigid</termName><termType>ND</termType></relation><relation><relationType>BT</relationType><termId>31414555</termId><termName>structures by property</termName><termType>PT</termType></relation></term>  </Zthes>