1. Araujo, J., Bratten, T.: On the spectrum of the Johnson graphs
$${J}(n,k,r)$$
J
(
n
,
k
,
r
)
. In: Proceedings of the XXIIrd “Dr. Antonio A. R. Monteiro” Congress, pp. 57–62 (2016). Univ. Nac. Sur Dep. Mat. Inst. Mat., Baha Blanca, 2015
2. Assmus Jr., E.F., Key, J.D.: Designs and Their Codes. Cambridge University Press, Cambridge (1992). Cambridge Tracts in Mathematics, Vol. 103 (Second printing with corrections, 1993)
3. Bosma, W., Cannon, J., Playoust, C.: The Magma algebra system I: the user language. J. Symb. Comput. 24(3/4), 235–265 (1997)
4. Brouwer, A., Haemers, W.: Association schemes. In: Graham, R., Grötschel, M., Lovász, L. (eds.) Handbook of Combinatorics, Chapter 15, Vol. 1, pp. 749–771. Elsevier; MIT, Cambridge (1995)
5. Cannon, J., Steel, A., White, G.: Linear codes over finite fields. In: Cannon, J., Bosma, W. (eds.) Handbook of Magma Functions, pp. 3951–4023. Computational Algebra Group, Department of Mathematics, University of Sydney (2006). V2.13.
http://magma.maths.usyd.edu.au/magma