diff --git a/postgres/between-symmetric.md b/postgres/between-symmetric.md
index 1292d97..34f926d 100644
--- a/postgres/between-symmetric.md
+++ b/postgres/between-symmetric.md
@@ -4,7 +4,9 @@ PostgreSQL's `between` construct allows you to make a comparison _between_
 two values (numbers, timestamps, etc.).
 
 ```sql
-> select * from generate_series(1,10) as numbers(a) where numbers.a between 3 and 6;
+> select *
+  from generate_series(1,10) as numbers(a)
+  where numbers.a between 3 and 6;
  a
 ---
  3
@@ -17,7 +19,9 @@ If you supply an empty range by using the larger of the two values first, an
 empty set will result.
 
 ```sql
-> select * from generate_series(1,10) as numbers(a) where numbers.a between 6 and 3;
+> select *
+  from generate_series(1,10) as numbers(a)
+  where numbers.a between 6 and 3;
  a
 ---
 ```
@@ -26,7 +30,9 @@ Tacking `symmetric` onto the `between` construct is one way to avoid this
 issue.
 
 ```sql
-> select * from generate_series(1,10) as numbers(a) where numbers.a between symmetric 6 and 3;
+> select *
+  from generate_series(1,10) as numbers(a)
+  where numbers.a between symmetric 6 and 3;
  a
 ---
  3
@@ -39,3 +45,5 @@ issue.
 > that the argument to the left of AND be less than or equal to the argument
 > on the right. If it is not, those two arguments are automatically swapped,
 > so that a nonempty range is always implied.
+
+[source](https://www.postgresql.org/docs/current/functions-comparison.html#:~:text=BETWEEN%20SYMMETRIC%20is%20like%20BETWEEN,nonempty%20range%20is%20always%20implied.)