1. Balonin, N.A., Seberry, J.: A review and new symmetric conference matrices. UDC 004.438 (2014)
2. Belevitch, V.: Theory of $$2n$$ 2 n -terminal networks with applications to conference telephony. Electron. Commun. 27, 231–244 (1950)
3. Coxeter, H.S.M.: Regular compound polytopes in more than four dimensions. J. Math. Phys. 12, 334–345 (1933)
4. Delsarte, P., Goethals, J.-M., Seidel, J.J.: Orthogonal matrices with zero diagonal II. Can. J. Math. XXII I(5), 816–832 (1971)
5. Dita, P.: Complex Hadamard matrices from Sylvester inverse orthogonal matrices. Roum. J. Phys. 54(5–6), 433–440 (2009)