<?xml version="1.0" encoding="utf-8"?><!DOCTYPE Zthes SYSTEM "http://zthes.z3950.org/xml/zthes-05.dtd">  <Zthes><term><termId>31420519</termId><termName>stereoviewers</termName><termType>PT</termType><termNote><![CDATA[ A stereoscopic viewing device that uses a wheel or reel of slides to present two images, isolated for each eye, that together create a three-dimensional optical effect. Invented by William Gruber in 1938 as an educational device, it has been marketed as a children's toy since that time under the trademarked name "View-Master." For the device used to view individual stereo cards, popular in the 19th century, use "stereoscopes." ]]></termNote><termCreatedDate>2026-03-30 20:53:18</termCreatedDate><relation><relationType>UF</relationType><termId>31420520</termId><termName>stereoviewer</termName><termType>ND</termType></relation><relation><relationType>UF</relationType><termId>31420521</termId><termName>view master</termName><termType>ND</termType></relation><relation><relationType>BT</relationType><termId>31386070</termId><termName>photograph viewing equipment</termName><termType>PT</termType></relation><relation><relationType>RT</relationType><termId>31299402</termId><termName>View-Masters (TM)</termName><termType>PT</termType></relation></term>  </Zthes>