SENTANG JAYA INDONESIA, PT North Sumatera SIR 20, SIR 3, SIR 5, Setiawan Khoe, Su Chin. setiawan_sri@yahoo.com (62-61) 4559941 www.sentangraya.com (62-811) 643679 (62-61) 4561844 Jl. Timur No. 23/14 C, Medan Timur