Template:Semple, Heard, & Brouillet, 2002
Semple, J.C., Heard, S.B., & Brouillet, L. 2002. Cultivated and native asters of Ontario (Compositae: Astereae): Aster L. (including Asteromoea Blume, Diplactis Raf. and Kalimeris (Cass.) Cass.), Callistephus Cass., Galatella Cass., Doellingeria Nees, Oclemena E.L.Greene, Eurybia (Cass.) S.F.Gray, Canadanthus Nesom, and Symphyotrichum Nees (including Virgulus Raf.). University of Waterloo Biology Series 41: 134 pp.