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Mosaic
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Breakthrough (5)
Missing in Death
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Eve Dallas (36)
The Eyes of Texas
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Mountain Man (8)
Short-Cut Math
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Dead Reckoning: Calculating Without Instruments
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More Rapid Math: Tricks and Tips: 30 Days to Number Mastery
Edward H. Julius
Rapid Math: Tricks and Tips: 30 Days to Number Mastery
The Trachtenberg Speed System of Basic Mathematics
Jakow Trachtenberg
Speed Mathematics Simplified
Edward Stoddard
How to Calculate Quickly: Full Course in Speed Arithmetic
Henry Sticker