— Appeal from a judgment of the Supreme Court at Special Term (Cobb, J.), entered January 17,1984 in Albany County, which, in a proceeding pursuant to CPLR article 78, granted respondent’s motion to dismiss the petition on the ground that it was untimely commenced. 11 The petition initiating this proceeding alleges a cause of action (1) for a judgment pursuant to CPLR article 78 to review a determination of respondent which sustained an assessment of sales and use taxes in the amount of $98,824.89, plus interest, and (2) for a declaratory judgment declaring that the application of regulation 20 NYCRR 528.9 (a) (4) to petitioner’s situation is unconstitutional. Special Term dismissed both actions as being untimely commenced. This appeal by petitioner ensued. H Respondent’s determination which sustained an assessment of sales and use tax was issued on April 1, 1983. Since the notice of petition and petition were served on August 11,1983, the proceeding was not commenced within four months of the date of the determination as required by CPLR 217 and section 1138 (subd [a], par [4] of the Tax Law. Accordingly, the cause of action seeking CPLR article 78 review of respondent’s determination was correctly dismissed by Special Term as being untimely. H With respect to the question of timeliness of petitioner’s second cause of action, seeking a declaration that 20 NYCRR 528.9 (a) (4) is unconstitutional, a reading of the petition leaves no doubt that petitioner’s challenge is to the constitutionality of regulation 20 NYCRR 528.9 (a) (4) as applied to petitioner’s interstate fleet operation. The wherefore clause of the
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If petitioner’s second cause of action was to be treated as a declaratory judgment action, such a conversion would be required since only a petition instituting a CPLR article 78 proceeding was served upon respondent; a separate action for a declaratory judgment was not commenced.