https://docs.asciidoctor.org/asciidoc/latest/syntax-quick-reference/
AsciiDoc Syntax Quick Reference | Asciidoctor Docs
The quick reference for common AsciiDoc document and text formatting markup.
syntax quick referenceasciidocdocs
https://docs.cloud.google.com/apigee/docs/api-platform/publish/portal/markdown-reference?authuser=1
Markdown syntax quick reference | Apigee | Google Cloud Documentation
syntax quick referencegoogle cloudmarkdownapigeedocumentation