With the additional module "Paid Articles" you have the possibility to offer individual contents, independent of editions. This not only generates additional income, but also offers users the option of buying only individual articles.
How to create articles and all other important information on this topic can be found here.
How can I offer paid articles?
To be able to offer an article as a Paid Article, you have to assign a price and a product ID to the article. For Apple and Google respectively. There you can also set the price. Finally, please activate the "Purchase required" button and click on "Create".