Nostalgia Dressia

I just couldn't stop taking photos of this dress! Look how good it looks in photos?

Sizeguide: This dress says it is a size 42 - but I am really not sure if it is an Italian size 42 or a French or a EU or say a Dutch or? And how much did sizes even change the past decades? It also just depends on your expectations for it! I can squeeze into it, and I would say my butt is perhaps a proud size 42 in the large understanding of a size 42.