<?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">sonar</topic></authority><related type="broader"><topic>exploring and investigating techniques</topic></related><variant type="other"><topic>anti-submarine detection investigation committee</topic></variant><variant type="other"><topic>asdic</topic></variant><variant type="other"><topic>echo ranging</topic></variant><variant type="other"><topic>echo sounding</topic></variant><variant type="other"><topic>ranging, echo</topic></variant><variant type="other"><topic>sound navigation ranging</topic></variant><variant type="other"><topic>sounding, echo</topic></variant> <note xml:lang="en"><![CDATA[ A method of detecting the presence of objects under water by means of sonic and ultrasonic waves that are reflected from the object. ]]></note></mads>