2019 and 2020 books are in the
Odds and Ends
6 10, 3:44pm
Actually you can get better than Wikipedia. Also, that article you just sent also states "however, the Danish Faroe Islands are sometimes included, as sometimes are Iceland and Finland, because of their historical association with the Scandinavian countries and the Scandinavian peoples and languages." You might also want to take a look at this.
Also, "Nordic languages" is not a language branch, it's a collective term of languages within the Nordics. Which are Scandinavian languages and Uralic languages.
And no, Scandinavia didn't always include just the three kingdoms. "Scandinavia" comes from the Germanic word Skaðinawja, which means "damaged island" and referred only to Skåne. You also have to understand that when the term rose to popularity in the 19. century, Iceland was a part of Denmark, meaning that Icelanders were legally people of Denmark as well, and therefore Scandinavians too. If you knew anything about Icelandic culture, history and language, you would know that Icelanders are also Scandinavians.