@article{ref1,
title="A problem in mining, together with some data on tunnel-driving",
journal="Transactions of the American Institute of Mining and Metallurgical Engineers",
year="1913",
author="Simonds, F. M. and Burns, E. Z.",
volume="45",
number="",
pages="147-180",
abstract="<p>[Abstract unavailable]</p><p>Language: en</p>",
language="",
issn="0096-4778",
doi="",
url="http://dx.doi.org/"
}