sugar cubes
... that sugar cubes were used to deliver the polio vaccine?
... that <b id="mwAxk"><a class="mw-redirect" href="./Cube_sugar" id="mwAxo" rel="mw:WikiLink" title="Cube sugar">sugar cubes</a></b> were used to deliver the <a href="./Polio_vaccine" id="mwAxs" rel="mw:WikiLink" title="Polio vaccine">polio vaccine</a>?