diff --git a/infra.bs b/infra.bs
index 800f0c2..2eaba15 100644
--- a/infra.bs
+++ b/infra.bs
@@ -1675,6 +1675,10 @@ a new ordered set |clone|, so that replacing "afoo" in |clone| gives « "foo", "b", "c" »,
while |original|[0] is still the string "a".
+
To reverse a list |list| is to create a new +list |reversed|, of the same designation, and, for each |item| of |list|, +prepend |item| to |reversed|. +
To sort in ascending order a list |list|, with a less than algorithm |lessThanAlgo|, is to create a new list |sorted|, containing the same items as |list| but sorted so that according to