Incidence algebra antipodes and lagrange inversion in one and several variables. - Mark D. Haiman; William Schmitt (J. Comb. Theory A, 1989)

Hopf Algebras and Identities in Free Partially Commutative Monoids. - William Schmitt (Theor. Comput. Sci., 1990)

Ultimate chromatic polynomials. - Nigel Ray; William Schmitt (Discret. Math., 1994)

The Whitney Algebra of a Matroid. - Henry Crapo; William Schmitt (J. Comb. Theory A, 2000)

The free product of matroids. - Henry Crapo; William Schmitt (Eur. J. Comb., 2005)

A free subalgebra of the algebra of matroids. - Henry Crapo; William Schmitt (Eur. J. Comb., 2005)

A unique factorization theorem for matroids. - Henry Crapo; William Schmitt (J. Comb. Theory A, 2005)