Despina A. Stylianou; Maria L. Blanton; Eric J. Knuth <br/><br/>
Teaching and Learning Proof Across the Grades  A K-16 Perspective 

 -  Taylor and Francis  2009 
<br/><br/><label>ISBN: </label>9780203882009 
<br/><br/><label>Source: </label>EBOOK