The British national killed when passenger plane crashed in Kazan, western Russia, has been described by her colleague as "a very popular and well-respected member of staff".
James Pitman, managing director for Study Group's higher education division, said A-levels programme manager Donna Bull "will be sorely missed by both her students and colleagues".
Mr Pitman confirmed the "very sad news" of Ms Bull's death and that of her Moscow-based colleague, Yana Baranova.
He said in a statement: "Donna had flown out from the UK to Moscow earlier in the day, where she met Yana, and the two were heading to Kazan for the start of a 10-day marketing trip."
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