ex.6 Use Google search engine to find this book(PDF file) post llink of these 2 books in your blog

1.http://www.oie.go.th/sites/default/files/attachments/IndustBasicKnowledge/Master_11.pdf

2.https://drive.google.com/file/d/1bnf_DPi-A_eO_vZSncyx2pYZqXKpnOjW/view?usp=sharing