Dominic Day
Dominic Day( born 22 August 1985) is a Welsh rugby union player.
Jean Day
Jean Day( born in 1954), is an American poet.
Dorothy Day (plant physiologist)
Dorothy Day( born 1896) was an American plant physiologist.
Tony Day
Tony Day( born 14 April 1965) is a British swimmer.
Alonso Mudarra
Alonso Mudarra( c. 1510 – April 1, 1580) was a Spanish composer of the Renaissance, and also played the vihuela, a guitar- shaped string instrument.
He was an innovative composer of instrumental music as well as songs, and was the composer of the earliest surviving music for the guitar.
Mark Day (actor)
Mark Day( born October 4, 1978) is a Canadian actor and producer.
Riley Day
Riley Day( born 30 March 2000) is an Australian sprinter.
It's a Hap-Hap-Happy Day
"It's a Hap-Hap-Happy Day" is a popular song with words by Sammy Timberg & Winston Sharples and music by Al J. Neiburg.
It was featured in the animated feature film "Gulliver's Travels" in 1939.
It was a hit in the UK in 1940 during the Battle of Britain, having been played heavily on the BBC radio.
Dalton Day
Dalton Day( born August 2, 1991) is an American actor and singer.
Al J. Neiburg
Allen J. Neiburg (November 22, 1902—July 12, 1978) was an American lyricist.
He was born on 22 November 1902 in St. Albans, Vermont and received his education at Boston University.
He is known for writing lyrics for such songs as "I'm Confessin' (That I Love You)"
(with Doc Dougherty and Ellis Reynolds), "It's the Talk of the Town" and "Under a Blanket of Blue" (with Jerry Livingston and Marty Symes).
He also ran his own publishing company.
Neiburg died in New Haven, Connecticut, on 12 July 1978.

Question: What is the place of birth of the composer of song It'S A Hap-Hap-Happy Day?