Mwesigwa, R., Sarvate, D. G., & Zhang, L. (2016). Group divisible designs of four groups and block size five with configuration (1; 1; 1; 2). Journal of Algebra Combinatorics Discrete Structures and Applications, 3(3), 187–194. Retrieved from https://jacodesmath.com/index.php/jacodesmath/article/view/47