Sheffield United have signed striker Billy Sharp from Leeds United and secured Derby County forward Conor Sammon on a season-long loan.
Sharp has joined for an undisclosed fee and signed a two-year contract with the option of an extra year.
The 29-year-old returns to Bramall Lane for a third spell having begun his career there in 2004 before playing for them again from 2007 to 2010.
"I'm looking forward to working with them," said Blades boss Nigel Adkins.
Republic of Ireland international Sammon, 28, has one year left on his contract with Derby.
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