Anatomy and essential oils from aerial organs in three species of Aldama (Asteraceae–Heliantheae) that have a difﬁcult delimitation - Bombo, Aline Bertolosi; Oliveira, Tuane Santos de; Oliveira, Adriana da Silva Santos; Rehder, Vera Lúcia Garcia; Magenta, Mara Angelina Galvão; Appezzato-da-Glória, Beatriz (Australian Journal of Botany, 2012)