1 Distributions on Toroidal Groups.- 2 Modular Units.- 3 Quadratic Relations.- 4 The Siegel Units Are Generators.- 5 The Cuspidal Divisor Class Group on X(N).- 6 The Cuspidal Divisor Class Group on X1 (N).- 7 Modular Units on Tate Curves.- 8 Diophantine Applications.- 9 Unramified Units.- 10 More Units in the Modular Function Field.- 11 Siegel-Robert Units in Arbitrary Class Fields.- 12 Klein Units in Arbitrary Class Fields.- 13 Computation of a Unit Index.- Appendix: The Logarithm of the Siegel Functions.
