Definition 89.25.1. Let $\mathcal{F}$ be a category cofibered in groupoids over a category $\mathcal{C}$. Let $(U, R, s, t, c)$ be a groupoid in functors on $\mathcal{C}$. A presentation of $\mathcal{F}$ by $(U, R, s, t, c)$ is an equivalence $\varphi : [U/R] \to \mathcal{F}$ of categories cofibered in groupoids over $\mathcal{C}$.

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