In his resignation statement to the National Assembly, Mr Middlehurst said the reason for his resignation was simple.

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Whatever the reason for his resignation, it is a good thing that Freeman was forced to resign.

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Deutsche Telecom (nyse: DT - news - people )has given no official reason for his resignation but it is almost certainly linked to his previous tenure as head of the communications division of Siemens (nyse: SI - news - people ), rather than his performance at T-Systems.

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Mr. Pitt has given his critics ample reason for demanding his resignation.

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Historians regard Celestine's claim of "personal infirmity" with considerable skepticism, focusing instead on "the malignity of the people" and pressure from his eventual successor as the real reason for his unprecedented resignation.

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Robertson, however, has refused to give a reason for or otherwise comment on his resignation.

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