On Lana Del Rey's page it counts Lizzie Grant as the years she was active. So English Wikipedia is correct on Gaga

It's not a mistake. She is a professional since 2008, that means she's active since then. She wasn't Lady Gaga before that.

stefani joanne's career is since 2005 with red and blue (second picture). lady gaga's career is since 2008 (first picture). everyone knows that gaga and stefani are the same person, but just some people know about red and blue in 2005. for the most of people, lady gaga is just lady gaga.

Gaga has been active after 2008 , then she's name Stefani Germanotta ;D

Oh, really. I dind't see the years...

ooooooooooooo

she has been active after 2008. she has been active as lady gaga not as stefani