Wittaya Hewararak และ Bunjerd Jongsomjit. (2011) Characteristics and catalytic properties of spherical zirconia-supported cobalt catalyst for methanation. Chulalongkorn University:ม.ป.ท.Wittaya Hewararak และ Bunjerd Jongsomjit. 2011. Characteristics and catalytic properties of spherical zirconia-supported cobalt catalyst for methanation. ม.ป.ท.:Chulalongkorn University;Wittaya Hewararak และ Bunjerd Jongsomjit. Characteristics and catalytic properties of spherical zirconia-supported cobalt catalyst for methanation. ม.ป.ท.:Chulalongkorn University, 2011. Print.