Rao, K. and Ramanujam, C. (1976) “Palynology of the Neogene Quilon beds of Kerala state in South India I - Spores of pteridophytes and pollen of monocotyledons”, Journal of Palaeosciences, 25(1-3), pp. 397–427. doi: 10.54991/jop.1976.1027.