VOLUME 7, PART 4 JULY 1966

PROCEEDINGSof the

GLASGOW MATHEMATICAL ASSOCIATIONPublished with the support of the University Court of the University of Glasgow

CONTENTS

J. P. Earl and J. R. Shackell, Note on the region of overconvergence ofDirichlet series with Ostrowski gaps 169

F. M. Ragab and M. A. Simary, Integrals involving ^-functions 174

H. K. Farahat, The semigroup of doubly-stochastic matrices 178

W. D. Munn and N. R. Reilly, Congruences on a bisimple co-semigroup 184

C. U. Jensen, A remark on the distributive law for an ideal in a com-mutative ring 193

A. Geddes and R. G. Walker, The structure of cancellative power-freegroups 199

R. G. Walker, Non-cancellative power-free groups 207

OLIVER AND BOYD

EDINBURGH:TWEEDDALE COURT

LONDON: 39A WELBECK STREET, W.I

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PROCEEDINGS OFTHE GLASGOW MATHEMATICAL ASSOCIATION

THE present part is the last number to be issued under the above title. From Volume 8,Part 1, the title of the periodical will be changed to the Glasgow MathematicalJournal,which will continue to be issued twice yearly, in January and July. The size of eachpart will be increased from approximately 48 pages to approximately 64 pages and anew Volume, consisting of two parts, will be issued annually.

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GLASGOW MATHEMATICAL JOURNAL

DEPARTMENT OF MATHEMATICS

UNIVERSITY OF GLASGOW, GLASGOW, W. 2

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