| With J. Z. Goncalves,
The proof of the Lichtman and Makar-Limanov Conjectures for Skew
Polynomial Rings, preprint.
 Finite perfect inner automorphism groups of division rings,
 Projective representations of groups, and the Brauer group, preprint.
 With H. J. Van Roessel, On a finite system of coagulation equations with time-dependent kernels and source terms,
 With H. J. Van Roessel, Existence and uniqueness of solutions of Smoluchowski's coagulation equation with source terms, Quarterly of Applied Mathematics, to appear.
 With H. J. Van Roessel, Some results on the coagulation equation, Nonlinear Analysis: Theory, methods, and Applications, 43 (2001), 563-573.
 With A. Mandel and J. Z. Goncalves, Free products of units in algebras. II. Crossed Products , J. Algebra, 233 (2000), 567-593.
 With J.Z. Goncalves, Large free algebras in the ring of fractions of skew polynomial rings, J. London Math. Soc., (2) 60 (1999), 481-489.
 With A. Mandel and J. Z. Goncalves, Free products of units in algebras. I. Quaternion algebras, J. Algebra 214 (1999), 301-316.
 With J. So, Solutions of linear differential algebraic equations, SIAM Review, 40 (1998), 344-346.
 With J.Z. Goncalves, On the codimension of the image of a derivation in a commutative field, Comm. in Algebra, 26 (1998), 2273-2281.
 With J.Z. Goncalves, Free group algebras in the field of fractions of differential polynomial rings snd enveloping algebras, J. Algebra, 204 (1998), 372-385.
 With A.I. Lichtman, HNN-extensions of Lie algebras, Proc. Amer. Math. Soc., 125 (1997), 3501-3508.
 With L.M.V. Figueiredo and J.Z. Goncalves, Free group algebras in certain division rings, J. Algebra 185 (1996), 298-313.
 With J. Z. Goncalves, On free group algebras in division rings with uncountable center, Proc. Amer. Math. Soc. 124 (1996), 685-687.
 The finite inner automorphism groups of division rings, Math. Proc. Camb. Phil. Soc. 118 (1995), 207-213.
 The structure of simple rings generated by finite metabelian groups, J. Algebra 169 (1994), 686-712.
 With H. J. Van Roessel, The mass-conserving solutions of Smoluchowski's coagulation equation, Z. angew Math. Phys. 43 (1992), 526-535.
 On conjugacy separability of fundamental groups of graphs of groups, Trans. Amer. Math. Soc. 334 (1992), 229-243.
 With T. D. Rogers, On ergodic one-dimensional cellular automata, Comm. Math. Phys. 136 (1991), 599-605.
 With K. E. Hare, The semisimplicity problem for p-adic group algebras, Proc. Amer. Math. Soc. 108 (1990), 653-664.
 With T. D. Rogers, An ergodic family of maps on sequence spaces, Physica D 44 (1990), 131-148.
 With B. A. F. Wehrfritz, On skew linear groups associated with certain soluble-by-finite groups, Can. Math. Bull. 32 (1989), 505-508.
 A converse to a residual finiteness criterion of G. Baumslag, Proc. Amer. Math. Soc. 104 (1988), 703-706.
 With T. D. Rogers, Ergodic endomorphisms of compact abelian groups, Comm. Math. Phys. 118 (1988), 401-410.
 With J. D. R. Stock, On mass conserving solutions of the discrete coagulation equation, J. Phys. A21 (1988), 1069-1078.
 On residually finite graph products of groups, J. Pure Appl. Algebra 49 (1987), 281-282.
 With B. A. F. Wehrfritz, "Skew Linear Groups", Cambridge University Press, 1986.
 On residually finite HNN-extensions, Arch. Math. 44 (1985), 110- 115.