Per Curiam.The employer and carrier produced no expert proof nor all of the documentary evidence apparently available and chose to rest their case on the issue of their witness’ veracity, as opposed to *981that of claimant, who denied signing the purported release. Questions of credibility are, of course, for the board; and upon the entire record we find no legal basis for a holding by us that the determination was not upon substantial evidence. Appellants’ single point is that the board was “without jurisdiction to declare the third party release invalid”, this in sole reliance upon Matter of Cristiano v. Ninfa’s Rest. (285 App. Div. 560); but the board’s determination in the case before us was not of invalidity and the authority cited is not relevant. Decision affirmed, with costs to the Workmen’s Compensation Board. Gibson, P. J., Reynolds, Taylor, Aulisi and Hamm, JJ., concur.