Streck, Nereu Augusto, et al. “Effect of Plant Density and Drastic Prunning on Tomato Yield Inside a Plastic Greenhouse”. Pesquisa Agropecuaria Brasileira, vol. 33, no. 7, July 1998, pp. 1105-12, https://doi.org/10.1590/S1678-3921.pab1998.v33.4940.