Pliszko, Artur. “Erigeron Acris L. Subsp. Angulosus (Gaudin) Vacc. (Asteraceae), a New Taxon in the Flora of Poland”. Acta Botanica Croatica 77, no. 1 (April 1, 2018). Accessed May 17, 2025. https://abc.botanic.hr/index.php/abc/article/view/1693.