## Contents of Volume 23, Number 2

HTML articles powered by AMS MathViewer

- Miscellaneous front pages, Bull. Amer. Math. Soc. (N.S.), Volume 23, Number 2 (1990)
- Bull. Amer. Math. Soc.
**23**(1990)

- Miscellaneous back pages, Bull. Amer. Math. Soc. (N.S.), Volume 23, Number 2 (1990)
- Bull. Amer. Math. Soc.
**23**(1990)

- Multiplication of distributions
- J. F. Colombeau PDF
- Bull. Amer. Math. Soc.
**23**(1990), 251-268

- Exponential sums over finite fields and differential equations over the complex numbers: Some interactions
- Nicholas M. Katz PDF
- Bull. Amer. Math. Soc.
**23**(1990), 269-309

- Elliptic methods in symplectic geometry
- Dusa McDuff PDF
- Bull. Amer. Math. Soc.
**23**(1990), 311-358

- Hurwitz groups: A brief survey
- Marston Conder PDF
- Bull. Amer. Math. Soc.
**23**(1990), 359-370

- Torsion points on elliptic curves
- S. Kamienny PDF
- Bull. Amer. Math. Soc.
**23**(1990), 371-373

- The behavior of the Mordell-Weil group of elliptic curves
- Armand Brumer and Oisín McGuinness PDF
- Bull. Amer. Math. Soc.
**23**(1990), 375-382

- A new upper bound for the minimum of an integral lattice of determinant 1
- J. H. Conway and N. J. A. Sloane PDF
- Bull. Amer. Math. Soc.
**23**(1990), 383-387

- $L$ functions for the group $G_2$
- I. Piatetski-Shapiro, S. Rallis and G. Schiffmann PDF
- Bull. Amer. Math. Soc.
**23**(1990), 389-399

- Subgroups of polynomial automorphisms
- Edwin Connell and John Zweibel PDF
- Bull. Amer. Math. Soc.
**23**(1990), 401-406

- Circle packings in the approximation of conformal mappings
- Kenneth Stephenson PDF
- Bull. Amer. Math. Soc.
**23**(1990), 407-415

- The topology of complete one-ended minimal surfaces and Heegaard surfaces in ${\text {R}}^3$
- Charles Frohman and William H. Meeks III PDF
- Bull. Amer. Math. Soc.
**23**(1990), 417-421

- A finiteness theorem for Ricci curvature in dimension three
- Shun-Hui Zhu PDF
- Bull. Amer. Math. Soc.
**23**(1990), 423-426

- Simply connected manifolds of positive scalar curvature
- Stephan Stolz PDF
- Bull. Amer. Math. Soc.
**23**(1990), 427-432

- Isospectral families of conformally equivalent Riemannian metrics
- Robert Brooks and Carolyn Gordon PDF
- Bull. Amer. Math. Soc.
**23**(1990), 433-436

- Complete noncompact Kähler manifolds with positive holomorphic bisectional curvature
- Wan-Xiong Shi PDF
- Bull. Amer. Math. Soc.
**23**(1990), 437-440

- Some new results on the topology of nonsingular real algebraic sets
- Selman Akbulut and Henry King PDF
- Bull. Amer. Math. Soc.
**23**(1990), 441-446

- Exotic cohomology and index theory
- John Roe PDF
- Bull. Amer. Math. Soc.
**23**(1990), 447-453

- The tensor product problem for reflexive algebras
- Jon Kraus PDF
- Bull. Amer. Math. Soc.
**23**(1990), 455-460

- Triangular algebras and ideals of nest algebras
- John Lindsay Orr PDF
- Bull. Amer. Math. Soc.
**23**(1990), 461-467

- Antimonotonicity: Concurrent creation and annihilation of periodic orbits
- I. Kan and J. A. Yorke PDF
- Bull. Amer. Math. Soc.
**23**(1990), 469-476

- A new formulation of the generalized Toda lattice equations and their fixed point analysis via the momentum map
- Anthony M. Bloch, Roger W. Brockett and Tudor S. Ratiu PDF
- Bull. Amer. Math. Soc.
**23**(1990), 477-485

- On the complete integrability of some Lax systems on ${\text {GL}}\left ( {n,R} \right ) \times {\text {GL}}\left ( {n,R} \right )$
- Luen-Chau Li PDF
- Bull. Amer. Math. Soc.
**23**(1990), 487-493

- A simplified version of the abstract Cauchy-Kowalewski theorem with weak singularities
- Russel E. Caflisch PDF
- Bull. Amer. Math. Soc.
**23**(1990), 495-500

- Zero-order perturbations of the subelliptic Laplacian on the Heisenberg group and their uniqueness properties
- Nicola Garofalo and Ermanno Lanconelli PDF
- Bull. Amer. Math. Soc.
**23**(1990), 501-511

- Subcriticality, positivity, and gaugeability of the Schrödinger operator
- Z. Zhao PDF
- Bull. Amer. Math. Soc.
**23**(1990), 513-517

- $L^p \to L^\{p’\}$ estimates for time-dependent Schrödinger operators
- J. L. Journé, A. Soffer and C. D. Sogge PDF
- Bull. Amer. Math. Soc.
**23**(1990), 519-524

- On the energy of a large atom
- Charles L. Fefferman and Luis A. Seco PDF
- Bull. Amer. Math. Soc.
**23**(1990), 525-530

- Shape optimization for Dirichlet problems: Relaxed solutions and optimality conditions
- Giuseppe Buttazzo and Gianni Dal Maso PDF
- Bull. Amer. Math. Soc.
**23**(1990), 531-535

- Discrete analogues of singular Radon transforms
- E. M. Stein and S. Wainger PDF
- Bull. Amer. Math. Soc.
**23**(1990), 537-544

##
Book Reviews

Book reviews do not contain an abstract. You may
download each review in this issue using the links
below.

- The linearization method in hydrodynamical stability theory, by V. I. Yudovich.
- Reviewer: D. H. Sattinger

- Review information PDF
- Bull. Amer. Math. Soc.
**23**(1990), 545-547

- $J$ Contractive matrix functions, reproducing kernel Hilbert spaces and interpolation, by Harry Dym.
- Reviewer: Joseph A. Ball

- Review information PDF
- Bull. Amer. Math. Soc.
**23**(1990), 547-551

- Operators and representation theory: Canonical models for algebras of operators arising in quantum mechanics, by P. E. T. Jorgensen.
- Reviewer: Roe Goodman

- Review information PDF
- Bull. Amer. Math. Soc.
**23**(1990), 551-554

- Initial-boundary value problems and the Navier-Stokes equations, by Heinz-Otto Kreiss and Jens Lorenz.
- Reviewer: Peter Constantin

- Review information PDF
- Bull. Amer. Math. Soc.
**23**(1990), 555-559

- Mathematical problems from combustion theory, by Jerrold Bebernes and David Eberly.
- Reviewer: A. K. Kapila

- Review information PDF
- Bull. Amer. Math. Soc.
**23**(1990), 559-562

- The asymptotic solution of linear differential systems, applications of the Levinson theorem, by M. S. P. Eastham.
- Reviewer: Allen Devinatz

- Review information PDF
- Bull. Amer. Math. Soc.
**23**(1990), 563-566

- Conformal geometry, by Ravi S. Kulkarni and Ulrich Pinkall.
- Reviewer: William M. Goldman

- Review information PDF
- Bull. Amer. Math. Soc.
**23**(1990), 566-575

- Real analysis and probability, by R. M. Dudley.
- Reviewer: Mark A. Pinsky

- Review information PDF
- Bull. Amer. Math. Soc.
**23**(1990), 575-579

- Noncommutative Noetherian rings, by J. C. McConnell and J. C. Robson.
- Reviewer: Edward Formanek

- Review information PDF
- Bull. Amer. Math. Soc.
**23**(1990), 579-582

- Foliations on Riemannian manifolds, by Philippe Tondeur.
- Riemannian foliations, by Pierre Molino.
- Reviewer: L. Conlon

- Review information PDF
- Bull. Amer. Math. Soc.
**23**(1990), 583-588

- Elementary geometry in hyperbolic space, by Werner Fenchel.
- Reviewer: J. B. Wilker

- Review information PDF
- Bull. Amer. Math. Soc.
**23**(1990), 589-594

- The classical groups and $K$-theory, by A. J. Hahn and O. T. O'Meara.
- Reviewer: Robert Steinberg

- Review information PDF
- Bull. Amer. Math. Soc.
**23**(1990), 594-598

- Harmonic analysis of spherical functions on real reductive groups, by R. Gangolli and V. S. Varadarajan.
- Reviewer: D. Barbasch

- Review information PDF
- Bull. Amer. Math. Soc.
**23**(1990), 598-604

- Binary quadratic forms, classical theory and applications, by D. A. Buell.
- Reviewer: D. H. Lehmer

- Review information PDF
- Bull. Amer. Math. Soc.
**23**(1990), 604-605

- The emperor's new mind, by Roger Penrose.
- Reviewer: John McCarthy

- Review information PDF
- Bull. Amer. Math. Soc.
**23**(1990), 606-616

- Cosmology in $\left( {2 + 1} \right)$-dimensions, cyclic models, and deformations of $M_{2,1}$, by Victor Guillemin.
- Reviewer: John K. Beem

- Review information PDF
- Bull. Amer. Math. Soc.
**23**(1990), 616-617

- The averaged moduli of smoothness with applications in numerical methods and approximation, by Blagovest Sendov and Vasil A. Popov.
- Reviewer: R. J. Nessel

- Review information PDF
- Bull. Amer. Math. Soc.
**23**(1990), 618-620

- Matrix norms and their applications, by G. R. Belitskii and Yu. I. Lyubich.
- Reviewer: Peter A. Fillmore

- Review information PDF
- Bull. Amer. Math. Soc.
**23**(1990), 620-623

- Vibration and coupling of continuous systems: asymptotic methods, by Jacqueline Sanchez Hubert and Enrique Sanchez Palencia.
- Reviewer: M. Slemrod

- Review information PDF
- Bull. Amer. Math. Soc.
**23**(1990), 623-626

- An introduction to the numerical analysis of spectral methods, by Bertrand Mercier.
- Reviewer: Levi Lustman

- Review information PDF
- Bull. Amer. Math. Soc.
**23**(1990), 626-629

- The theory of fixed point classes, by Kiang Tsai-Han.
- Reviewer: D. R. Smart

- Review information PDF
- Bull. Amer. Math. Soc.
**23**(1990), 630-633