
Are the following mentions coreferent?:
<m> replacing </m> in Matt Smith, 26, will make his debut in 2010, replacing David Tennant, who leaves at the end of this year. He is the youngest actor to play the part. He has previously appeared on TV, in films and the theatre and is best known for appearing in the BBC's The Ruby in the Smoke. 
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<m> take over </m> in A relative unknown will take over the title role of Doctor Who in the British science fiction television show, making him the 11th time lord in 45 years to travel across the universe in the Tardis time-ship. 