TOPSHOT - A woman holds a sign reading "In memomy of Mamoudou Barry" as she takes part in a white march in front of the University of Rouen on July 26, 2019 in hommage to Mamoudou Barry, a young Guinean teacher and researcher killed a week before during a "racist" aggression, according to his family. - Mamoudou Barry, 31 years old, succumbed to his wounds after being beaten up in a street of Canteleu, near Rouen on July 19, 2019. (Photo by LOU BENOIST / AFP)