1. Arasu, K.T., Xiang, Q.: On the existence of periodic complementary binary sequences. Des. Codes Cryptogr. 2, 257–262 (1992)
2. Balonin, N.A., Djoković, D. Ž: Symmetry of two-circulant Hadamard matrices and periodic Golay pairs, (in Russian) Inf. Control Syst. 3, 2–16 (2015)
3. Bosma, W., Cannon, J.: Handbook of Magma Functions. University of Sydney, Department of Mathematics (1994). http://magma.maths.usyd.edu.au/magma
4. Crnković, D.: Symmetric (70,24,8) designs having $${\rm Frob}_{21} \times Z_2$$ as an automorphism group. Glas. Mat. Ser. III 34(54), 109–121 (1999)
5. Crnković, D., Danilović, D Dumičić, Rukavina, S.: On symmetric (78,22,6) designs and related self-orthogonal codes. Util. Math. 109, 227–253 (2018)