Pilar Rodríguez Agustín Yagüe Pedro Pablo Alarcón Juan Garbajosa Some Findings Concerning Requirements in Agile Methodologies. 171-184 2009 PROFES http://dx.doi.org/10.1007/978-3-642-02152-7_14 conf/profes/2009 db/conf/profes/profes2009.html#RodriguezYAG09