Title:      ``Relative Homological Algebra and Purity in Triangulated categories". 
                
Status:     To appear in  Journal of Algebra. 
              
               Updated version  of the 1998 preprints  ``Relative Homological Algebra in
               Triangulated categories I, II" 
                                        
Author:    Apostolos Beligiannis.

Address:  7th Sintagmatos 21, 34100 Chalkis, Evia, Greece.
                                                          and
                Department of Mathematics, University of the Aegean, 83200 Karlovasi, Samos,
                Greece.