Piriya Pholphirul. 2013. Happiness from giving: A quantitative investigation from Thai buddhists. Bangkok:National Institute of Development Administration;
Piriya Pholphirul. (2013) Happiness from giving: A quantitative investigation from Thai buddhists (รายงานผลงานวิจัย). National Institute of Development Administration:Bangkok.
Piriya Pholphirul. Happiness from giving: A quantitative investigation from Thai buddhists. Bangkok:National Institute of Development Administration, 2013.
Piriya Pholphirul. (2013) Happiness from giving: A quantitative investigation from Thai buddhists (รายงานผลงานวิจัย). National Institute of Development Administration:Bangkok.