University of Isfahan Transactions on Combinatorics 2251-8657 2 3 2013 09 01 On the nomura algebras of formally self-dual association schemes of class $2$ 1 11 3002 10.22108/toc.2013.3002 EN Azam Hosseini Department of Mathematics, K. N. Toosi University of Technology Amir Rahnamai Barghi K. N. Toosi university of Technology University, Tehran-Iran. Journal Article 2013 05 21 ‎‎In this paper‎, ‎the type-<em>II</em> matrices on (negative) Latin square graphs are considered and it is proved that‎, ‎under‎ ‎certain conditions‎, ‎the Nomura algebras of such type<em>-II</em> matrices are trivial‎. ‎In addition‎, ‎we construct type-<em>II</em> matrices‎ ‎on doubly regular tournaments and show that the Nomura algebras of such matrices are also trivial‎. ‎Doubly regular tournament‎ ‎Nomura algebra‎ ‎strongly regular graph‎ ‎type-II matrix https://toc.ui.ac.ir/article_3002_619911c64aa82c9a4401803498c0f325.pdf