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by Erin OpreaHardcover details (USA). details (UK). details (Germany). details (Canada). ISBN: 978-1-101-90308-7 ISBN-10: 1-101-90308-2 Harmony · 2016  | 
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| 2018 | Paperback | The 4 x 4 Diet: 4 Key Foods, 4-Minute Workouts, Four Weeks to the Body You Want |