The Welfare Analysis of Oil Palm Smallholder Farmers in Pangkalan Banteng Sub-District, Central Kalimantan Heri Setyawan, Indra Kurniawan, Koko Setiawan, Herry Listianto Buletin Penelitian Sosial Ekonomi Pertanian Fakultas Pertanian Universitas Haluoleo Vol. 22 No. 1 2020 DOI 10.37149/bpsosek.v22i1.13292