diff --git a/relational-data.Rmd b/relational-data.Rmd
index bf6af4b..b5019e1 100644
--- a/relational-data.Rmd
+++ b/relational-data.Rmd
@@ -106,7 +106,7 @@ There are two types of keys:
   each plane in the `planes` table.
 
 * A __foreign key__ uniquely identifies an observation in another table.
-  For example, the `flights$tailnum` is a foreign key because it appears in the 
+  For example, `flights$tailnum` is a foreign key because it appears in the 
   `flights` table where it matches each flight to a unique plane.
 
 A variable can be both a primary key _and_ a foreign key. For example, `origin` is part of the `weather` primary key, and is also a foreign key for the `airport` table.