The new LuhmannImport handles just one single resource (the famous Zettelkasten), but with its wealth of cross references, this is a good example to show and exercise three different formats. See more in my non-technical blog, https://x28newblog.wordpress.com/2019/06/21/zettelkasten-visualized/
(Currently, it is only available in the Java versions, not in the DMG, MSI, or web demo.)