diff --git a/src/sage/manifolds/subset.py b/src/sage/manifolds/subset.py
index 8597d433a56..0acc6c907b7 100644
--- a/src/sage/manifolds/subset.py
+++ b/src/sage/manifolds/subset.py
@@ -1381,9 +1381,14 @@ def declare_subset(self, *supersets):
             sage: P = M.subset_poset()
             sage: P.plot(element_labels={element: label(element) for element in P})
             Graphics object consisting of 9 graphics primitives
+
+        Subsets in a directed cycle of inclusions are equal::
+
             sage: M.declare_subset(V)
             sage: M.superset_family()
             Set {M, U1, U2, V} of open subsets of the 2-dimensional differentiable manifold M
+            sage: M.equal_subset_family()
+            Set {M, U1, U2, V} of open subsets of the 2-dimensional differentiable manifold M
             sage: P = M.subset_poset()
             sage: P.plot(element_labels={element: label(element) for element in P})
             Graphics object consisting of 2 graphics primitives
@@ -1442,9 +1447,14 @@ def declare_superset(self, *subsets):
             sage: P = M.subset_poset()
             sage: P.plot(element_labels={element: label(element) for element in P})
             Graphics object consisting of 11 graphics primitives
+
+        Subsets in a directed cycle of inclusions are equal::
+
             sage: W.declare_superset(U)
             sage: W.subset_family()
             Set {U, V1, V1_inter_V2, V2} of open subsets of the 2-dimensional differentiable manifold M
+            sage: W.equal_subset_family()
+            Set {U, V1, V1_inter_V2, V2} of open subsets of the 2-dimensional differentiable manifold M
             sage: P = M.subset_poset()
             sage: P.plot(element_labels={element: label(element) for element in P})
             Graphics object consisting of 4 graphics primitives