. J. R. T. . MALUF, . R. . MATZENAUER, and . M. R. . CAIAFFO, “CORN AGRO CLIMATIC ZONING BY SOWING DATES IN THE STATE OF RIO GRANDE DO SUL, BRAZIL ”, PESQ. AGROP. GAÚCHA, vol. 6, no. 1, pp. 39–54, Aug. 2000.