The article discusses corrections to equations in two papers by Onoda & Kawada and Onoda, Saeki & Kawada, regarding the mis-expression of exponential terms in X-ray diffraction calculations. The corrections involve replacing all instances of exp(-i2πζ), exp(-iπζ/2), exp(-iπζ), and exp(-i3πζ/2) with their positive counterparts. The International Union of Crystallography has appointed Professor A. J. C. Wilson as Chairman of the Commission on International Tables and Editor for a proposed revision of Volumes II, III, and IV. The revised International Tables for Crystallography, covering 17 plane groups and 230 space groups, is expected to be published in mid-1983. The volume includes comprehensive tables and an introduction on symmetry, with a cost of 385 Netherlands Guilders. Personal copies are available at a reduced price. The Twelfth International Congress of Crystallography included a session on crystallographic statistics, with 15 papers published by the Indian Academy of Sciences. The book "Crystallographic Statistics: Progress and Problems" is edited by S. Ramaseshan, M. F. Richardson, and A. J. C. Wilson. Book reviews are invited for publication. The book "Nonlinear Phenomena at Phase Transitions and Instabilities" is edited by R. Riste and covers topics such as non-linear excitations, thermal convection, turbulence, and crystal growth.The article discusses corrections to equations in two papers by Onoda & Kawada and Onoda, Saeki & Kawada, regarding the mis-expression of exponential terms in X-ray diffraction calculations. The corrections involve replacing all instances of exp(-i2πζ), exp(-iπζ/2), exp(-iπζ), and exp(-i3πζ/2) with their positive counterparts. The International Union of Crystallography has appointed Professor A. J. C. Wilson as Chairman of the Commission on International Tables and Editor for a proposed revision of Volumes II, III, and IV. The revised International Tables for Crystallography, covering 17 plane groups and 230 space groups, is expected to be published in mid-1983. The volume includes comprehensive tables and an introduction on symmetry, with a cost of 385 Netherlands Guilders. Personal copies are available at a reduced price. The Twelfth International Congress of Crystallography included a session on crystallographic statistics, with 15 papers published by the Indian Academy of Sciences. The book "Crystallographic Statistics: Progress and Problems" is edited by S. Ramaseshan, M. F. Richardson, and A. J. C. Wilson. Book reviews are invited for publication. The book "Nonlinear Phenomena at Phase Transitions and Instabilities" is edited by R. Riste and covers topics such as non-linear excitations, thermal convection, turbulence, and crystal growth.