@inproceedings{Herberthson07a,
author = {M. Herberthson and A. Brun and H. Knutsson},
title = {Representing pairs of orientations in the plane}, 
booktitle = {Proceedings of the 15th Scandinavian conference on image analysis (SCIA'07)},
year= {2007}, 
address = {Aalborg, Denmark},
}