Villarreal, J. C., Cargill, D. C., Hagborg, A., Soderstrom, L., & Renzaglia, K. S. (2014). A synthesis of hornwort diversity: Patterns, causes and future work. Phytotaxa, 9(1), 150–166. https://doi.org/10.11646/phytotaxa.9.1.8