@TechReport{JanotaEtAl08, author = {Mikol\'a\v{s} Janota and Joseph Kiniry and Goetz Botterweck}, title = {Formal Methods in {Software Product Lines}: Concepts, Survey, and Guidelines}, institution = {Lero, University of Limerick}, year = 2008, number = {Lero-TR-SPL-2008-02}, month = may }