I highly recommend this one:
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Patchwork Minus the Mathwork: A Quilter's Guide to Planning and Buying Fabrics without a Degree in Mathmatics! by Jeanne Stauffer (Nov 20, 2009)[/h]
I use it all the time to figure out measurements and how much fabric to buy.
I also use this great reference book to carry in my travel case. It comes in so handy at workshops and retreats:
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All-In-One Quilter's Reference Tool Easy-To-Follow Charts, Tables and Illustrations, Yardage Requirements, Cutting Instructions, Setting Secrets, Choosing ... Piecing Techniques, Number Conversions by
Harriet Hargrave, Sharyn Craig, Alex Anderson and Liz Aneloski (Oct 1, 2004)[/h]