N.Y. Comp. Codes R. & Regs. tit. 19, § 178.5 – Prohibited forms of solicitation.

(a) Within a nonsolicitation area, no real estate broker or real estate salesperson shall engage in any form of solicitation where the purpose of such solicitation is, directly or indirectly, to obtain a listing of residential property for sale and where such solicitation is directed at or toward a homeowner or occupant of residential property within a designated nonsolicitation area.
(b) The following are examples of the types of solicitation that are prohibited:
1. (1) letters;
2. (2) postcards;
3. (3) handbills or leaflets or fliers;
4. (4) direct advertising delivered by mail or other service;
5. (5) telephone calls;
6. (6) door-to-door calls; and
7. (7) postings in public places.
(c) The following is not prohibited by a nonsolicitation order. Advertisements that are published in newspapers of general circulation:
1. (1) if such newspaper has a general readership throughout the metropolitan New York City area or throughout a substantial portion of the metropolitan New York City area;
2. (2) if such newspaper is published not less than once per week; and
3. (3) if such newspaper is sold by subscription or by individual copy and is not distributed free of charge.