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G.J.Anderson, ?Brittonia 27: 220. 1975.?, 1975.

Ugent, ?Phytologia 31: 18. 1975.?, 1975.

Lundell, ?Wrightia 5: 184. 1975?, 1975.

Lundell, ?Wrightia 5: 185. 1975?, 1975.

F.Chiang, ?Bol. Soc. Bot. México 35: 3 (-4), fig. 1975?, 1975.

(D. ) H. & Pickersgill, ?Baileya 19: 156. 1975?, 1975.