A Brief Top-Down and Bottom-Up Philosophy on Software Evolution Markus Pizka, Andreas Bauer IN PROCEEDINGS OF THE INTERNATIONAL WORKSHOP ON PRINCIPLES OF SOFTWARE EVOLUTION (IWPSE), KYOTO, JAPAN, SEPTEMBER 2004. IEEE COMPUTER SOCIETY. https://itestra.com/wp-content/uploads/2018/03/04_itestra_brief_top_down_bottom_up_philosophy.pdf