“…This is an interesting point because then the study of the quotient space associated to each grid becomes easier. To this end given a fenestration E of a space X, there is a canonical way to associate a pseudogrid × to E by identifying two points of X if and only if , for every open neighborhood of either, there exists an open neighborhood of the other one which intersects the same collection of elements of E. It is proved in [3] (Theorem 6.2.) that × is the minimal grid associated to E if and only if × is a grid, that is, is a lower semicontinuous decomposition.…”