Papers on time it takes to reach market equilibrium?
There is the famous Cobweb model. Starting from a situation of equilibrium, it analyses the effect of a shock, and how long it takes to reach the equilibrium, which depends entirely on the elasticities (or slopes) of demand and supply. Thus, by estimating empirically such elasticities for a given period (e.g. year), you can predict/forecast how many periods (e.g. years) it will take the market to settle after a shock. (Strictly speaking, it is infinity, but you just need to select a threshold or margin of error to consider the market in equilibrium)

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A huge literature exploded after the original paper, so if you google Cobweb models you get tons of hits. A very good treatment of this model can be found in Waugh (1964). He extends the simple model to multiple markets.