Ruschel, A. P., Filho, A. S., Santos, A. B. dos, & Zimmermann, F. J. P. (2014). Pigmentation and mineral composition of different <i>Azolla</i> species. Pesquisa Agropecuaria Brasileira, 24(4), 431–436. https://doi.org/10.1590/S1678-3921.pab1989.v24.15522