  We list defining relations for the four of the five exceptional simple Lie
superalgebras some of which, as David Broadhurst conjectured and Kac
demonstrated, may pertain to The Standard Model or Grand unified theories of
elementary particles. For the fifth superalgebra the result is not final: there
might be infinitely many relations. Contrariwise, for the same Lie superalgebra
with Laurent polynomials as coefficients there are only finitely many
relations.
