
    In the Matter of Westbury Union Free School District, Petitioner, v New York State Public Employment Relations Board et al., Respondents.
   Proceeding pursuant to CPLR article 78 to review a determination of the respondent New York State Public Employment Relations Board (PERB), dated November 21, 1975, which, after a hearing, (1) found that petitioner had violated section 209-a of the Civil Service Law and (2) ordered it to negotiate in good faith with the respondent Westbury Teachers Association. Determination confirmed and proceeding dismissed on the merits, with one bill of costs jointly to respondents appearing separately and filing separate briefs. There is substantial evidence in the record in this proceeding to support the determination of PERB. The failure of the public employer to reduce to writing (and then to execute) the oral agreement as to sabbatical leaves, attained after collective negotiation, constituted an improper employer practice, as contemplated by section 209-a of the Civil Service Law (see Heinz Co. v Labor Bd., 311 US 514; Art Metals Constr. Co. v National Labor Relations Bd., 110 F2d 148; Matter of New York State Labor Relations Bd. v Roosevelt Chevrolet Co., 177 Mise 468, 474-475; cf. Matter of Elwood Union Free School Dist. v Helsby, 45 AD2d 963). The effectiveness of such agreement is not relevant to the requirement that it be set forth in a formal writing and executed (see Civil Service Law, § 201, subd 12; § 204-a). Latham, Acting P. J., Margett, Rabin, Titone and Hawkins, JJ., concur.  