
Are the following mentions coreferent?:
<m> stepping into </m> in With young British actor Matt Smith stepping into Doctor Who's title role, Wired.com takes a look back at the 10 actors who have previously portrayed sci-fi TV's most enduring hero. 
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<m> stepped into </m> in When Matt Smith stepped into Doctor Who's title role as the 11th Doctor this weekend, he went from British character actor to potential entertainment legend. 