Quoc, N.A., Tri, N.M., Nghieu, N.T., Dinh, P.T., Chien, D.V. and Hoang, D.T. 2021. The nature of liberty. Linguistics and Culture Review. 5, S2 (Sep. 2021), 831-847. DOI:https://doi.org/10.21744/lingcure.v5nS2.1455.