Bradford have signed Carlisle striker Charlie Wyke and Huddersfield defender Jacob Hanson on permanent deals, plus defenders Matthew Penney and Kevin Toner on loan deals.
Wyke, 24, scored 32 league goals in 77 league games for the Cumbrians.
Both he and 19-year-old Hanson have joined for undisclosed fees on two-and-a-half-year deals.
Penney, 18, from Sheffield Wednesday, and Toner, 20, from Aston Villa, will stay until the end of the season.
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