Separated sets written as union of disjoint closed sets can be separated
110832
$F_\sigma$-subsets in a normal space can be separated
41611
Open and closed set in n by n matrices space.
33859
How to show that a disjoint sum of metric spaces is metrizable?
103106
Proving that any permutation in $S_n$ can be written as a product of disjoint cycles
24685
Expressing a Countable Union of Sets as the Countable Union of Disjoint Sets (e.g. Eliminating Duplicate Intersections)
5323
Example to show the distance between two closed sets can be 0 even if the two sets are disjoint
120376
Schema of separation and set of all sets
15480
Open set in a metric space is union of closed sets
93952
Show that $X$ can be represented as a union of disjoint equivalence classes
72750
Uncountable number of mutually disjoint countable sets in $\mathbb R$
123090
How to show that disjoint closed sets have disjoint open supersets?
148399
Two sets which contain each other as elements
28683
Sum of two closed sets in $\mathbb R$ is closed?
33117
Cyclic containment of sets
127678
A partition of the unit interval into uncountably many dense uncountable subsets
63276
Is an arbitrary union of a chain of countable sets countable?
80156
Formatting the union of sets