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Hassler, Michael & Schmitt, Bernd (August 2019), "Plenasium angustifolium", Checklist of Ferns and Lycophytes of the World, Version 8.10, diarsipkan dari asli tanggal 2017-09-02, diakses tanggal 2019-10-01
PPG I (2016). "A community-derived classification for extant lycophytes and ferns". Journal of Systematics and Evolution. 54 (6): 563–603. doi:10.1111/jse.12229. S2CID39980610.
Hassler, Michael & Schmitt, Bernd (August 2019), "Plenasium angustifolium", Checklist of Ferns and Lycophytes of the World, Version 8.10, diarsipkan dari asli tanggal 2017-09-02, diakses tanggal 2019-10-01