DarlanN. H., SiregarH. H., ListiaE., and SutartaE. S., “<strong>RECENT EVALUATION OF RISING TEMPERATURE AND OIL PALM EXTENSION TO HIGHER ELEVATION IN NORTH SUMATRA</strong><br&gt;(EVALUASI TERKINI KENAIKAN SUHU DAN PERLUASAN TANAMAN KELAPA SAWIT KE DATARAN TINGGI DI SUMATERA UTARA)”, Agromet, vol. 23, no. 2, pp. 112-122, Dec. 2009.