Hernandez, L.F. and Larsen, A.O. 2013. Visual definition of physiological maturity in sunflower (Helianthus annuus L.) is associated with receptacle quantitative color parameters. Spanish Journal of Agricultural Research. 11, 2 (Apr. 2013), 447-454. DOI:https://doi.org/10.5424/sjar/2013112-3645.