...S.Ansoldi1
E-mail address: ansoldi@trieste.infn.it 
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...A.Aurilia2
E-mail address: aaurilia@csupomona.edu 
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...E.Spallucci3
E-mail address: spallucci@trieste.infn.it 
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...-brane4
Here and in the following, by convention, ``$p$'' stands for the order of the simplex, or the spatial dimension of its image, so that a $p$-brane is really a $(p+1)$-dimensional submanifold in spacetime. 
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... length5
The necessity and role of a minimum length in quantum gravity is reviewed in Ref. [14]. 
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