@article{cometti_martins_bremenkamp_nunes_2011,  title={Nitrate concentration in lettuce leaves depending on photosynthetic photon flux and nitrate concentration in the nutrient solution},  volume={29},  ISSN={0102-0536},  url={https://doi.org/10.1590/S0102-05362011000400018},  DOI={10.1590/S0102-05362011000400018},  number={4},  journal={Horticultura Brasileira},  publisher={Associação Brasileira de Horticultura},  author={Cometti, Nilton Nélio and Martins, Madlles Q and Bremenkamp, Cintia Aparecida and Nunes, José Arcanjo},  year={2011},  month={Oct},  pages={548–553} }