What does W stand for in the name W. Rex Black?

Wilford Rex Black (January 31, 1920 – December 12, 2012) was an American politician.

Wilford Rex Black represented the 2nd Utah Senate District from 1973 to 1997. W. Rex Black, as he was often referred to, was a member of the Democratic party and represented the party as the Minority leader in the Utah Senate for many years.

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