Sakloetsakun, Duangkamon, and Andreas Bernkop Schnürch. 2017. “Effect of aliphatic and aromatic thiolated chitosan conjugates on permeability of ritonavir across caco-2 cell monolayers and rat intestinal membrane”. Asia-Pacific Journal of Science and Technology 17 (3):469-79. https://so01.tci-thaijo.org/index.php/APST/article/view/83260.