CONTENTS Introduction Part I. Generalized Jacobi conditions 1. The regular representation. Elementary examples 2. Quasi-commutation relations 3. Quadratic relations. Reduction to triangular form 4. The spectrum and cospectrum Part II. Quantization of the cospectrum 5. The spectrum and cospectrum of quadratic-linear relations 6. The transformation of the scale and structure constants by a graded semigroup 7. Algebras equivalent to Lie algebras. L-operator equations References