@article{Levine1990,
author = {Levine, R.J. and Mathew, R.M. and Chenault, C.B. and Brown, M.H. and Hurtt, M.E. and Bentley, K.S. and Mohr, K.L. and Working, P.K.},
title= {Differences in the quality of semen in outdoor workers during summer and winter},
year = {1990},
doi = {10.1056/NEJM199007053230103},
volume = {323},
number = {1},
pages = {12--16},
}