A. S. Rao, S. R. Rathore, and S. C. Srivastava, “<i>Didymoplexis pallens</i> Griff - Rediscovery of a Rare Saprophytic Orchid in the Indian Botanic Garden, Howrah”, Nelumbo, vol. 21, no. 1-4, pp. 151–155, Aug. 2015.