PARVENDER SHEORAN, et al. “Optimizing Sulphur Application in Sunflower (Helianthus Annuus) under Irrigated Semi-Arid Tropical Conditions”. Indian Journal of Agronomy, vol. 58, no. 3, Oct. 2001, pp. 384-90, https://doi.org/10.59797/ija.v58i3.4204.