@article{ref1,
title="Hierarchical Conflict Detection in Air Traffic Control",
journal="International journal of aviation psychology",
year="2005",
author="Rantanen, Esa M. and Nunes, Ashley",
volume="15",
number="4",
pages="339-362",
abstract="[Abstract unavailable]  <p>Language: en</p>",
language="en",
issn="1050-8414",
doi="10.1207/s15327108ijap1504_3",
url="http://dx.doi.org/10.1207/s15327108ijap1504_3"
}