This is the submitted version of the article: Dougherty, Steven T.; Fernández-Córdoba, Cristina; Ten-Valls, Roger; [et al.]. «Quaternary group ring codes : ranks, kernels and self-dual codes». Advances in Mathematics of Communications, Vol. 14, issue 2 (May 2020), p. 319-332. 14 pàg. DOI 10.3934/amc.2020023 This version is available at https://ddd.uab.cat/record/239907 under the terms of the license