The Two Worlds of Don Rosa
- Compares the different versions of Don Rosa stories.
- http://duckman.pettho.com/2worlds/

The D.U.C.K.man
- Sections include: Introductions to Don Rosa and his work, biographies of known and less known characters, a guide to the history of Duckburg, a presentation of the clan McDuck, comparison of Duck family trees, and information on story codes.
- http://duckman.pettho.com/

D.U.C.K.hunt
- The most comprehensive web site about Don Rosa.
- http://www.duckhunt.de/

D.U.C.K.burg
- Fan site with articles, interviews, images, downloads, news, and links.
- http://www.duckburg.dk/