Velázquez, J., Rosales, A., Rodríguez, H. and Salas, R. 2015. Determining the stages of tillering stage, initiation of primordia, flowering and maturity in the rice plant, with the system S, V and R correlated with the thermal sum at the time. Agronomía Costarricense. 39, 2 (Nov. 2015). DOI:https://doi.org/10.15517/rac.v39i2.21781.