In the internet there are many references about other Gotrek & Felix appearances in various books / magazines that are wrong.
Here is a list of the most common of them :
Novels (that it is wrongly stated that Gotrek & Felix appear) :
Vampire Wars : The Von Carstein Trilogy by Steven Savile : A trilogy consisting of the following books: Retribution, Inheritance, Dominion. These are Warhammer novels, taking place long before Gotrek & Felix roamed the world. Gotrek & Felix are NOT mentioned in these books.
Curse of the Necrarch by Steven Savile : Gotrek and Felix are NOT mentioned in this novel.
Short Story / Novella :
A Place Of Quiet Assembly : in internet is mentioned that this story is also in White Dwarf #140 (1991). This is wrong! The issue has some info about the duo (such as Gotrek’s birth year(!), etc.) but not this story. And as we read in the Introduction of Hammer And Bolter #1, this was an unpublished story until 2010!
Warhammer Supplements :
Warhammer Annual 2002 : It is mentioned that Gotrek & Felix are in the Dogs of War section. This is wrong! They appear in the Special Characters section.
White Dwarf Magazines :
Issues: 250, 251,252, 320 : There isn’t anything there (apart from advertisements of the books, such as from White Dwarf #252, page 13).
Warhammer Armies :
Daemons of Chaos(2007) : It is written that Gotrek & Felix appear in this book (History section). Gotrek and Felix are NOT mentioned in this book.
