Pintusorn Onpium และ Kanokkarn Kaewnuch. (2017) Promoting the value of Lanna cultural heritage tourism resources for Thai youth tourists. National Institute of Development Administration:ม.ป.ท.Pintusorn Onpium และ Kanokkarn Kaewnuch. 2017. Promoting the value of Lanna cultural heritage tourism resources for Thai youth tourists. ม.ป.ท.:National Institute of Development Administration;Pintusorn Onpium และ Kanokkarn Kaewnuch. Promoting the value of Lanna cultural heritage tourism resources for Thai youth tourists. ม.ป.ท.:National Institute of Development Administration, 2017. Print.