Boonyo, Worawan, Hans E. Junginger, Neti Waranuch, Assadang Polnok, and Tasana Pitaksuteepong. 2017. “Preparation and Characterization of Particles from Chitosan With Different Molecular Weights and Their Trimethyl Chitosan Derivatives for Nasal Immunization”. Journal of Metals, Materials and Minerals 18 (2). Bangkok, Thailand. https://www.jmmm.material.chula.ac.th/index.php/jmmm/article/view/312.