Given a short bio of a person, find the minimal text span containing the date of birth of the person. The output must be the minimal text span that contains the birth date, month and year as long as they are present. For instance, given a bio like 'I was born on 27th of Decemeber 1990, and graduated high school on 23rd October 2008.' the output should be '27th of December 1990'.
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Question: Thomas Jacob Black was born in Santa Monica, California, on August 28, 1969, the son of satellite engineers Thomas William Black and Judith Love Cohen

Answer: August 28, 1969


Question: On 19 August 1946, Ti was born as Tam Fu Wing (譚富榮) in Xinhui, Guangdong Province, China into a family with 4 members including himself, his parents and a younger sister

Answer: On 19 August 1946


Question: Keira Christina Knightley was born on 26 March 1985 in the Teddington suburb of London, to stage actors Will Knightley and Sharman Macdonald

Answer:
26 March 1985