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		| First Author:
 
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		| Marcelo Brutti Righi | 
	
		| Universidade Federal de Santa Maria | 
	
		| marcelobrutti@hotmail.com | 
	
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		| Santa Maria, 97015-372, Brazil | 
	
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		| +55 55 32209258(Phone) | 
	
		| +55 55 32209258(Fax) | 
	
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		| Second Author: 
 
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		| Paulo Sergio  Ceretta | 
	
		| Universidade Federal de Santa Maria | 
	
		| ceretta10@gmail.com | 
	
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