Add link refererence and footnote examples

src/content/docs/topics/writingsystems/another-writing-systems-page.md

@@ -0,0 +1,9 @@
+---
+title: Another writing systems page
+description: Another writing systems page to show linking
+sidebar:
+    order: 1100.1
+---
+
+This is another page only used as the target of example links.
+

src/content/docs/topics/writingsystems/what-is-a-writing-system.md

@@ -9,7 +9,20 @@ lastUpdated: 2024-10-22
 
 Basic definition of a writing system as script + language.
 
+Here is an example an external link to the [OpenType Specification][OTSpec].
+
+Here is an example of a link to [another page][Another] in this topic.
+
+Here is an example of a link to [a page somewhere else on this site][Somewhere].
+
+This refers to a footnote [^1] below.
+
 Here is the familiar map to demonstrate how images work:
 
 ![Scripts Around the World](../../../../assets/scriptsworldno1040ortext.png)
 
+[^1]: This is the footnote text.
+
+[OTSpec]: https://www.microsoft.com/typography/otspec/
+[Another]: ../another-writing-systems-page
+[Somewhere]: ../../fonts/example