R. Bacher et B. Venkov, LATTICES AND ASSOCIATION SCHEMES - A UNIMODULAR EXAMPLE WITHOUT ROOTSIN DIMENSION-28, Annales de l'Institut Fourier, 45(5), 1995, pp. 1163
Some interesting lattices can be constructed using association schemes
. We illustrate this by a unimodular lattice without roots of dimensio
n 28 which admits Sp(6, F-3) 2 as its automorphism group.