อ้างอิง
sites.google.com/site/somyoschamnongsooth/prawatisastr/kar-baeng-yukh-smay-thang-prawatisastr
www.paiduaykan.com/province/north/phichit/hpk_pichit.html
academic.obec.go.th/textbook/web/images/book/1003884_example.pdf
sites.google.com/a/nonedu2.go.th/sutatip/kar-nab-chwng-wela-pen-thswrrs-stwrrs-laea-shaswrrs