Medeiros, A.A.de, and H.P. Haag. 1990. “ Critical Level of Phosphorus in Cotton Varieties: III. Concentration of Phosphorus in the Leaves and Petioles Correlated With Time of Sampling ”. Anais Da Escola Superior De Agricultura Luiz De Queiroz 47 (1): 107-33. https://doi.org/10.1590/S0071-12761990000100007.