The editors of the three published (A, B, C) and the four proposed volumes of International Tables reported on the present status and the future plans of their volumes.

Th. Hahn demonstrated two new features of the Fourth Edition (1996)
of Volume A, *Space-Group Symmetry*: completion of the space-group
diagram project for all 17 plane and 230 space groups, and
introduction of the *double glide plane* *e* by means of new graphical
symbols for 17 space-group diagrams and modifications of five
orthorhombic space-group symbols.

The plans for the Second Edition of Volume B, *Reciprocal Space*,
were presented by the editor U. Shmueli. In addition to corrections
and major revisions of several existing chapters the Second Edition
will contain five new contributions on the following topics:

- Space-group representations in reciprocal space.
- Direct methods in electron crystallography.
- Diffraction by polymers.
- Reciprocal-space images of aperiodic crystals.
- Dynamical theory of neutron diffraction.

The editor of Volume C, *Mathematical, Physical and Chemical Tables*,
E. Prince, explained that the preparations for the Second Edition of
this Volume (scheduled for publication in 1997) were about 85%
complete at the time of death of the previous editor, A.J.C. Wilson.
The rest is presently being edited. Due to rapid obsolence of much of
the tabular material in this volume, an electronic version of Vol. C
is presently under active consideration.

The new Volume D, *Physical Properties of Crystals*, scheduled for
1998, was introduced by its editor A. Authier. It consists of three
parts:

- Part 1 treats Tensorial Aspects of Physical Properties; it contains both the general mathematical background and the individual physical properties.
- Part 2 is devoted to the Symmetry Aspects of Excitations (phonons, electrons, Raman scattering, Brillouin scattering).
- Part 3 is devoted to the Symmetry Aspects of Structural Phase Transitions, Twinning and Domain Structures.

The new Volume E, *Subperiodic Groups*, is edited by V. Kopsky and
D.B. Litvin. Its publication is planned for 1998. The volume is
devoted mainly to Layer and Rod Groups, i.e. to groups in three
dimensions with lattices of only two or one dimensions.

The volume consists of two parts:

- Part 1: Subperiodic group tables: Frieze, Rod and Layer Groups.
- Part 2: Scanning of space groups, i.e. layer groups as subgroups of space groups.

Volume A1, *Maximal Subgroups of Space and Plane Groups*, was
introduced by its editor H. Wondratschek. It is a companion volume to
Vol. A and completes the treatment of the maximal subgroups of space
groups. Complete lists of maximal subgroups of indices 2, 3, and 4
will be given. The infinitely many maximal isomorphic subgroups will
be presented by formulae with the index as parameter. Classes of
conjugate subgroups will be indicated.

The final project of the session was presented by T. Janssen: Volume
A2, *N-Dimensional Crystallography*. This volume consists of a
computer programme (CD-ROM) and an accompanying printed volume with a
manual and a treatment of the theory of symmetry in arbitrary
dimension. This implies that it gives the information on two- and
three-dimensional point groups as well. For more than three
dimensions these groups are used already by crystallographers dealing
with incommensurate phases and quasicrystals. From a data base are
calculated the space groups, the symmetry elements, the Wyckoff
positions, the general and special extinction rules, in short all
that can be found in the existing tables for 2 and 3 dimensions.

Updated 3 July 1997

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