Anilkumar, K., K. Kumar, and P. Udayan. “CEPF Western Ghats Special Series: Caralluma Bicolour Ramach. Et al., (Apocynaceae: Asclepiadoideae) - a Rare and Little Known Endemic Plant As a New Record from Palakkad District, Kerala State, India”. Journal of Threatened Taxa, vol. 5, no. 15, Nov. 2013, pp. 5007-9, doi:10.11609/JoTT.o3274.5007-9.