Meningkatkan hasil belajar siswa melalui model kooperatif numbered heads together (NHT) di kelas X SMA negeri 1 Beduai Kabupaten Sanggau ( Improving students achievements by using cooperative models of numbered haeds together (NHT) at class X of public senior hight school 1 Beduai Sanggau ([Publisher not identified] , [Date of publication not identified] )