Acknowledgements

This work would not have been possible without the use of the New Jersey/Warsaw evolutionary code and W Dziembowski's non-adiabatic pulsation code. We are very grateful to both Drs A Pamyatnykh and W Dziembowski for permission to use these codes. We are also very grateful to Dr R L Kurucz for sending us a CDROM with the latest model atmospheres. We would also like to thank Dr C Sterken for allowing us to use his unpublished data for V853 Cen Drs T Moon and M. Dworetsky for supplying their computer code.

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