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Hydrocharis morsus-ranae
Studies on the stomata of Hydrocharis Bot.
by Shinobu R. (1954)
Ruyiji Shinobu, Osaka Liberal Arts University
in Bot. Mag. Tokyo. 67. 73-77 –
https://www.jstage.jst.go.jp/article/jplantres1887/67/789-790/67_789-790_73/_article