Niwat Tontakul และ Pichaya Rachdawong. (2011) Carbon footprint of flat and long steel products. Chulalongkorn University:ม.ป.ท.Niwat Tontakul และ Pichaya Rachdawong. 2011. Carbon footprint of flat and long steel products. ม.ป.ท.:Chulalongkorn University;Niwat Tontakul และ Pichaya Rachdawong. Carbon footprint of flat and long steel products. ม.ป.ท.:Chulalongkorn University, 2011. Print.