The three-member South Korean boy band, High4, released in 2014 a song they collaborated with which South Korean singer, songwriter and actress who signed with LOEN Entertainment in 2007?
High4: High4 (hangul: 하이포; stylized as HIGH4) is a three-member South Korean boy band under the management of N.A.P Entertainment. High4:  They officially debuted into the Korean entertainment industry on April 8, 2014 with the song "Not Spring, Love, or Cherry Blossoms" featuring IU. IU (singer):  She signed with LOEN Entertainment in 2007 as a trainee and began her music career at the age of 15 with her debut album, "Lost and Found".
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