SIAHAAN, A. J.; IRSAL; SITORUS, B. The Relationship between Climate and Productivity of Tea Plants (Camellia sinensis L.) in Bah-Butong Gardens PT. Perkebunan Nusantara IV, North Sumatra Province in 2005-2009. Jurnal Online Pertanian Tropik, v. 11, n. 2, p. 1-8, 15 Aug. 2024.