It is no secret that Carl Barks sometimes took already published material and used it to fit his requirements when making his comic book stories for the Disney duck universe. This does not mean that he willfully plagiarized material; he merely used basic ideas that he himself could develop for his own purposes. Barks fetched ideas from a number of different main sources*, 10 of which are found in the sub-pages. These are divided into two main groups, in no special order, each consisting of 5 sections as you can see below. The 10 sections all represent examples of Barks' borrowings; surely you can come up with more sections and more examples if you wish.

* Sometimes Barks even borrowed ideas from - Barks! This website has several pages to that effect some of which are The Parallels, The Recycling, and The Repetitions.