New York Tax Law (Consolidated Laws)
N.Y. Tax Law § 1449-MMM — Apportionment
§ 1449-mmm. Apportionment. The local law adopted by the legislative\nbody of the county of Nassau shall provide for a method of apportionment\nfor determining the amount of tax due whenever the real property or\ninterest therein is situated within and without the county of Nassau.\n
Source: official text