On Hilbert's 17th problem and Pfister's multiplicative formulae for the ring of real analytic functions Article Sidebar Download Article PDF Download Article Abstract PDF Submitted: Jan 9, 2012 Accepted: Mar 29, 2012 Published: Jun 16, 2014 DOI: https://doi.org/10.2422/2036-2145.201201_004 Issue 2014: VOL. XIII, ISSUE 2 Section Article Main Article Content Francesca Acquistapace Fabrizio Broglia José F. Fernando Abstract Article Details