diff --git a/docs/entityRelationshipDiagram.md b/docs/entityRelationshipDiagram.md
index 4213cd9b6..0aa882424 100644
--- a/docs/entityRelationshipDiagram.md
+++ b/docs/entityRelationshipDiagram.md
@@ -195,6 +195,24 @@ The `type` and `name` values must begin with an alphabetic character and may con
 
 Attributes may also have a `key` or comment defined. Keys can be "PK" or "FK", for Primary Key or Foreign Key. And a `comment` is defined by quotes at the end of an attribute. Comments themselves cannot have quote characters in them.
 
+```
+erDiagram
+    CAR ||--o{ NAMED-DRIVER : allows
+    CAR {
+        string allowedDriver FK 'The license of the allowed driver'
+        string registrationNumber
+        string make
+        string model
+    }
+    PERSON ||--o{ NAMED-DRIVER : is
+    PERSON {
+        string driversLicense PK 'The license #'
+        string firstName
+        string lastName
+        int age
+    }
+```
+
 ```mermaid
 erDiagram
     CAR ||--o{ NAMED-DRIVER : allows