BibTex format
@article{Pfenninger:2014:10.1016/j.rser.2014.02.003,
author = {Pfenninger, S and Hawkes, A and Keirstead, J},
doi = {10.1016/j.rser.2014.02.003},
journal = {Renewable and Sustainable Energy Reviews},
pages = {74--86},
title = {Energy systems modeling for twenty-first century energy challenges},
url = {http://dx.doi.org/10.1016/j.rser.2014.02.003},
volume = {33},
year = {2014}
}