BioStor
 | Review of the taxonomy of Aster sensu lato (Asteraceae: Astereae), emphasizing the New World species G L Nesom Phytologia 77: 141-297 |
 | Chromosome counts of and notes on some Old World Asters (Asteraceae) A G Jones and R A Smogor (1983) Phytologia 53: 429-432 |