Gowthaman, K. et al. 2021. Cyclic DNA codes over the ring $\mathbb{Z}_4+u\mathbb{Z}_4+u^2\mathbb{Z}_4$. Journal of Algebra Combinatorics Discrete Structures and Applications. 8, 3 (Sep. 2021), 219–231. DOI:https://doi.org/10.13069/jacodesmath.1000959.