@conference{Faltings1991,
title = { Qualitative Models in Conceptual Design: A Case Study},
author = {Boi Faltings},
editor = {Gero, J.},
year = {1991},
date = {1991-00-00},
booktitle = {Artificial Intelligence in Design '91},
publisher = {Butterworth-Heinemann},
keywords = {},
pubstate = {published},
tppubtype = {conference}
}

@conference{Faltings1991a,
title = {Applying Means-Ends Analysis to Spatial Planning},
author = {Boi Faltings and P. Pu},
year = {1991},
date = {1991-00-00},
booktitle = { Proceedings of the IEEE/RSJ International Workshop on Intelligent Robots and Systems},
pages = {80-85},
publisher = {IEEE Press},
organization = {IEEE},
keywords = {},
pubstate = {published},
tppubtype = {conference}
}

@article{faltings90a,
title = {Qualitative Kinematics in Mechanisms},
author = {Boi Faltings},
year = {1990},
date = {1990-00-00},
journal = {Artificial Intelligence},
volume = {44},
number = {1},
pages = {89-119},
keywords = {},
pubstate = {published},
tppubtype = {article}
}