N.Y. Comp. Codes R. & Regs. tit. 16, § 683.4 – Records.

(a) The books of account of all radio-telephone utilities shall be kept by the double entry method, on an accrual basis. Each utility shall keep its accounts current and shall close its books at the end of each calendar year.
(b) All books of account, together with records and memoranda supporting the entries in the books of account, shall be kept in such a manner as to support fully the facts pertaining to such entries. The books and records referred to in this section include not only the accounting records in a limited technical sense, but also all other records, reports, correspondence, invoices, memoranda and information useful in determining the facts regarding a transaction.
(c) Utilities may further subdivide any of the accounts, provided that such subdivisions do not impair the integrity of the accounts.
(d) Except as authorized by the commission, all operating, accounting, or financial records, books, invoices, stubs, maps or documents shall be retained permanently.
(e) All such records shall be accessible, at all times, to the authorized representatives of the commission at a location within the State of New York.
(f) Attention is directed to the following extract from the Public Service Law:
Section 102, subdivision 1. “Every telegraph corporation and every telephone corporation, and all officers, agents and employees of any telegraph corporation or telephone corporation shall obey, observe and comply with every order, direction or requirement made by the commission, under authority of this article, so long as the same shall be and remain in force. Any telegraph corporation or any telephone corporation which shall violate any provision of this article, or which fails, omits or neglects to obey, observe or comply with any order or any direction or requirement of the commission, shall forfeit to the people of the State of New York, not to exceed the sum of one thousand dollars for each and every offense; every violation of any such order or direction or requirement, or of this article, shall be a separate and distinct offense, and, in case of a continuing violation, every day's continuance thereof shall be and be deemed to be a separate and distinct offense.”