Links

            Site sobre Ernst Mach     

                http://www.marxists.org/reference/subject/philosophy/works/ge/mach.htm 

            Site da Universidade de Viena

                www.univie.ac.at/

            Site sobre Ernst mach

                http://spaceboy.nasda.go.jp/note/kagaku/e/kag125_mach_e.html 

             Site sobre Josef Popper 

                www.friesian.com/popper.htm

             Site sobre Ludwig Boltzmann

                www.mrs.umn.edu/~sungurea/introstat/history/w98/Boltzmann.html