Schubert polynomials are a linear basis of the ring of polynomials in
x(1),..., x(n) with coefficients in y(1),..., y(n). We describe the mu
ltiplicative structure (multiplication by a single variable) of this s
pace. We also describe the structure of the ring as a free module of r
ank n! over the ring of symmetric polynomials in x,,..., x,. (C) 1997
Academic Press.