Submission of manuscripts by diskette We are pleased to announce that authors of this journal will from now on have the option of submitting accepted, final manuscripts in machine-readable form. We can handle most word-processing systems and disk formats. Instructions for preparation can be found on the information pages at the back of this issue. Please note th at the usual preparation method as hardcopy alone will always be possible. You may rest assured that the final quality of the printed article will remain the same whether it originates from a compuscript submission or submission as hardcopy. We expect that the production times--presently around four to five m o n t h s - - c a n be further reduced when this new process has been fully implemented. We hope that many of our regular authors will take up this opportunity of submitting their manuscripts in electronic form. The Publisher