chore(docs): update using-gatsby-without-graphql.md (#10952)

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## Description

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docs/docs/using-gatsby-without-graphql.md

@@ -101,3 +101,7 @@ If you're building a small site, one efficient way to build it is to pull in uns
 
 1.  Check out the [Plugin Library](/packages/) to see if the source plugins and/or transformer plugins you'd like to use already exist
 2.  If they don't exist, read the [Plugin Authoring](/docs/plugin-authoring/) guide and consider building your own!
+
+## Further reading
+
+Amberley Romo's guide to [using Gatsby without GraphQL](/blog/2018-10-25-using-gatsby-without-graphql/)