... regular Hadamard matrix of order 4 and H is a regular Hadamard matrix of order 9 · 4d+1. Therefore, one can obtain a family of regular Hadamard matrices of order 9 · 4d, starting with a regular ... Yamada, Hadamard matrices, sequences, and block designs, in ContemporaryDesign Theory, eds. J.H. Dinitz and D.R. Stinson, John Wiley & Sons, 1992, 431–560. New symmetric designs from regular Hadamard ... CRCPress, 1996.[4] J. D. Fanning, A family of symmetric designs, Discrete Mathematics 146 (1995), pp. 307–312.[5] Y.J. Ionin, Symmetric subdesigns of symmetric designs, Journal of Combinatorial Mathematicsand...