http://www.legislation.gov.uk/aip/Geo3/40/38/section/wrapper4Act of Union (Ireland) 1800An Act for the Union of Great Britain and Ireland.1978-02-01texttext/xmlenStatute Law Database2011-05-261991-02-01Article Third.One parliament.
That it be the third article of union, that the said united kingdom be represented in one and the same parliament, to be stiled “The parliament of the united kingdom of Great Britain and Ireland.”