N.Y. Family Court Act § 472: Undertaking to be filed

§ 472. Undertaking to be filed. If the property securing the

undertaking consists of real estate, the undertaking shall be filed with

the county clerk of the county in which the real estate is located and

the same shall constitute a lien upon the real estate specified in the

undertaking. The county clerk of each county is hereby directed to

accept such undertakings for filing and to provide proper and sufficient

books and indexes wherein the same shall be entered.