Khanthong, Preecha. " The Applicationofthe Quality Management System of ISO 9001: 2008 in the Improvement of the Water Suppliy Services of Municipal Waterworks Authority of Tak Fah Subdistrict Municipality, Nakhornsawan Province" Naresuan University Journal: Science and Technology (NUJST) [Online], Volume 22 Number 3 (17 October 2019)