... galaxies

Tables 3 and 4 and Figs. 11 and 12 are only available in electronic form at http://www.edpsciences.org

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...2,

Now at Institute of Astronomy, University of Edinburgh, Royal Observatory, Blackford Hill, Edinburgh, EH9 3HJ.

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... centre

For Abell 1451 we have adopted the X-ray peak as the centre of the cluster.

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...

Available only in the electronic version.

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...

Available only in the electronic version.

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