DescriptionCarduusflowerdiagram.png flower diagram of Carduus Date scanned 25 June 2006 Source Strasburger, Noll, Schenck, Schimper: Lehrbuch der Botanik
DescriptionCarduus floral diagram.svg English: based on https://commons.wikimedia.org/wiki/File:Carduus_flowerdiagram.png, adapted to the style of Ronse