glacial periods
...that glacial periods, commonly referred to as ice ages, are actually cold intervals within an ice age?
...that <b id="mwCGY"><a href="./Glacial_period" id="mwCGc" rel="mw:WikiLink" title="Glacial period">glacial periods</a></b>, commonly referred to as <a href="./Ice_age" id="mwCGg" rel="mw:WikiLink" title="Ice age">ice ages</a>, are actually cold intervals <i id="mwCGk">within</i> an ice age?