Experience Report on the Effect of Market Reposition on Product Line Evolution. - Razvan T. Dumitrescu; Antonio J. Bailetti; Samuel Ajila (IRI, 2004)

Experimental use of code delta, code churn, and rate of change to understand software product line evolution. - Samuel Ajila; Razvan T. Dumitrescu (J. Syst. Softw., 2007)