A differentiable stack X may be equipped with Grothendieck topology in a certain way (see the reference).
Robert Stack | Harry Stack Sullivan | Frank Stack | Charles M. Stack | Timothy Stack | stack | Needle in a Slunk Stack | Jack Stack | Differentiable manifold | Stack-oriented programming language | stack interchange | stack (geology) | Stack Exchange Network | Stack (data structure) | South Stack | Robert Stack's | Phil Stack | Kelli Stack | James T. Grady-James H. Stack Award for Interpreting Chemistry | Brian Stack | Anaconda Smelter Stack | Aindrias Stack |