Engineer [Mix Assistant] – Phil SeafordEngineer [Mix] – John HanesMixed By – Serban GheneaProducer – Carl Falk , Rami YacoubWritten-By – Carl Falk , Rami, Savan Kotecha

Mixed By – Manny MarroquinMixed By [Assistant] – Chris Galland, Erik MadridProducer, Arranged By – Steve MacWritten-By – August Rigo, Steve Mac

Mixed By – Serban GheneaProducer – Carl Falk , Rami YacoubWritten-By – Carl Falk , Rami, Savan Kotecha

Mixed By – Ash HowesProducer – Brian Rawling, Paul MeehanWritten-By – Jamie Scott

Mixed By – Serban GheneaProducer – Matt SquireWritten-By – Matt Squire, Savan Kotecha

Mixed By – Serban GheneaProducer – Carl Falk , Rami YacoubWritten-By – Carl Falk , Rami, Savan Kotecha

Mixed By – Ash HowesProducer – Shep Solomon*, Tom MeredithWritten-By – Kelly Clarkson, Shep Solomon*, Tom Meredith

Mixed By – Ash HowesProducer, Engineer – Toby GadWritten-By – Harry Styles, Liam Payne, Lindy Robbins, Louis Tomlinson, Niall Horan, Toby Gad, Zain Malik

Mixed By – Ash HowesProducer – Ash Howes, Richard "Biff" Stannard*Written-By – Tom Fletcher

Mixed By – Serban GheneaProducer – Steve RobsonWritten-By – Harry Styles, Liam Payne, Louis Tomlinson, Niall Horan, Steve Robson, Wayne Hector, Zain Malik

Producer, Mixed By – Steve RobsonWritten-By – Harry Styles, Liam Payne, Louis Tomlinson, Niall Horan, Steve Robson, Wayne Hector, Zain Malik

Mixed By – Orlando CalzadaProducer – BeatGeek, Jimmy Joker, RedOneWritten-By – AJ Junior, Alaina Beaton, BeatGeek, Jimmy Joker, RedOne, Savan Kotecha, Teddy Sky

Mixed By – Matt FurmidgeProducer – Brian Rawling, Paul MeehanWritten-By – Jamie Scott, Paul Meehan