Team, Support. 2015. “Factorisable Monoid of Generalized Hypersubstitutions of Type $\tau=(2)$: Ampika Boonmee, Sorasak Leeratanavalee”. Thai Journal of Mathematics 13 (1):213-25. https://thaijmath2.in.cmu.ac.th/index.php/thaijmath/article/view/503.