Are birds reptiles???

hey guys..recently I received my biology paper from yourhomeworkhelp.org/biology-homework-help/ and there I read a weird thing about birds being reptiles..surely I didn't trusted it and googled but it turns out some scientists do thinks birds are reptiles (scienceline.ucsb.edu/getkey.php?key=1292 , askabiologist.asu.edu/questions/birds-dinosaurs-reptiles )..what do you think??