Information:  - Amorphis is a Finnish heavy metal band founded by Jan Rechberger, Tomi Koivusaari, and Esa Holopainen in 1990. Initially, the band was a death metal act, but on later albums they evolved into playing other genres, including heavy metal, progressive metal, and folk metal. They frequently use the Kalevala, the Epic Poem of Finland, as a source for their lyrics.  - Tomi Koivusaari (11 April 1973) is the current rhythm guitarist and former vocalist of the Finnish metal band Amorphis. He started playing at the age of 12, his first band was Violent Solution formed in 1987, with him on guitars and vocals, Esa Holopainen on guitars and Jan Rechberger on drums. The band played thrash metal, recorded a demo and an EP. He also formed a death/doom band called Abhorrence in 1989, and recorded a demo and an EP. Both bands broke up in 1990, but Tomi was not a member of Violent Solution since he formed Abhorrence.  - Tomi Koivusaari ( April 11 , 1973 ) is the current rhythm guitarist and former vocalist of the Finnish metal band Amorphis . He started playing at the age of 12 , his first band was Violent Solution formed in 1987 , with him on guitars and vocals , Esa Holopainen on guitars and Jan Rechberger on drums . The band played thrash metal , recorded a demo and an EP . He also formed a death / doom band called Abhorrence in 1989 , and recorded a demo and an EP . Both bands broke up in 1990 , but Tomi was not a member of Violent Solution since he formed Abhorrence . In 1990 , Tomi was hired to be in Amorphis . In 2006 , Tomi was briefly in the band Ajattara , under the name `` Samuel Lempo '' .  - Esa Holopainen (born 1 October 1972) is a Finnish musician, currently the main songwriter, occasional lyricist, founding member and lead guitarist of the Finnish metal band Amorphis.  He is one out the two longest standing members of the band (the other being Tomi Koivusaari) and one of the three out of four original members left in the band (the others being Jan Rechberger and Tomi Koivusaari).    Given the information above, choose from the list below the object entity that exhibits the relation 'date of birth' with the subject 'tomi koivusaari'.  Choices: - 1 october 1972  - 11  - 11 april 1973  - 12  - 1972  - 1987  - 1990
Answer:
11 april 1973