Noppadon Sinpaisansomboon และผู้แต่งคนอื่นๆ. (2007) Development of Two-Stage Anaerobic Digesters for Biogas Production from Biodegradable Waste of Phitsanulok Municipal, Thailand. <i>International Journal of Renewable Energy</i>, <i>Vol. 2</i>(No.2), pp 63-71.Noppadon Sinpaisansomboon และผู้แต่งคนอื่นๆ. "Development of Two-Stage Anaerobic Digesters for Biogas Production from Biodegradable Waste of Phitsanulok Municipal, Thailand". International Journal of Renewable Energy Vol. 2 (2007):pp 63-71.Noppadon Sinpaisansomboon และผู้แต่งคนอื่นๆ. Development of Two-Stage Anaerobic Digesters for Biogas Production from Biodegradable Waste of Phitsanulok Municipal, Thailand. School of Renewable Energy Technology:ม.ป.ท. 2007.