@ARTICLE{
author={Milani Andrea,Gronchi Giovanni F,Vitturi MD,Knezevic Zoran},
year={2004},
title={Orbit determination with very short arcs. I - Admissible regions},
journal={CELESTIAL MECHANICS & DYNAMICAL ASTRONOMY},
volume={90},
number={1-2},
pages={59-87},
document_type={Article},
}