When the Ninth Doctor tried to mimic Jackie Tyler, Rose told him "Dick Van Dyke wants his accent back." (COMIC: Weapons of Past Destruction)
When the Tenth Doctor mockingly said that he was convinced by "the whole posh, gravelly thing" present in the War Doctor's voice, the Eleventh Doctor said to his predecessor, "Brave words, Dick Van Dyke", implying that the younger Doctor had no cause to comment upon the authenticity of someone's voice. (TV: The Day of the Doctor)
Behind the scenes[]
The reference in both stories comes from the fact that Dick Van Dyke, an American, is roundly ridiculed in the United Kingdom for his poor Cockney accent in the film Mary Poppins. The joke also works on a meta-textual level since David Tennant played the Tenth Doctor with Estuary English (which sounds similar to Cockney) instead of his natural Scottish accent.
Apart from starring in Mary Poppins and Chitty Chitty, Bang Bang, Dick Van Dyke is best known for The Dick Van Dyke Show, which guest starred Jeremy Clyde in one episode, who would later go on to voice Tony Clare in Stranded.