@article {BirkHellerJohn+03a,
author={Andreas Birk and Gerald Heller and Isabel John and Thomas von der Maßen and Klaus Müller and Klaus Schmid},
title={Product Line Engineering: The State of the Practice},
journal={IEEE Software},
number={6},
volume={20},
year={2003},
pages={52-60},
abstract={Software product lines are powerful tools for ensuring quality, economic efficiency, and manageability of families of software systems. SPL is important for many companies in the software business, ranging from small start-ups to large industrial enterprises. However, SPL is also a challenging technology that's not always easy to implement and maintain. Members from five different organizations formed a work group that investigated and compared their SPL practices over a period of two and a half years. The group identified key practice areas including organization and support, balancing platform versus client interests, requirements engineering practices, and architecture. The investigation's results detail the SPL state of the practice.}
}