Concave Set: Mathematics, Convex Set, Complement (mathematics)

Sigma ring: Mathematics, Complement (Set Theory)

Hilbert Metric: Mathematics, Metric (mathematics), Convex Set, Euclidean Space

Concave Function: Function, Mathematics, Additive Inverse, Convex Function

Algebra of Sets: Set (mathematics), Union (set theory), Intersection Complement Binary relation, Equality (mathematics)