18 cities in the Soviet Union had a population of at least one million
... that 18 cities in the Soviet Union had a population of at least one million in 1979?
... that <b id="mwBI0"><a class="mw-redirect" href="./Soviet_Census_(1979)" id="mwBI4" rel="mw:WikiLink" title="Soviet Census (1979)">18 cities in the Soviet Union had a population of at least one million</a></b> in 1979?