\usepackage{url}
@article{ cox:science_2004,
    author={Cox, D. D. and Meyers, E. and Sinha, P.},
    title={{Contextually evoked object-specific responses in human visual cortex}},
    journal={Science},    
    volume={304},
    number={5667},
    pages={115-117},
    
    url={http://www.rowland.harvard.edu/cox/pdfs/Science_CoxMeyersSinha_2004.pdf},
    year={2004}
}