BibTex format
@article{Joffe:2005:aje/kwi172,
author = {Joffe, M and Key, J and Best, N and Keiding, N and Scheike, T and Jensen, TK},
doi = {aje/kwi172},
journal = {AMERICAN JOURNAL OF EPIDEMIOLOGY},
pages = {115--124},
title = {Studying time to pregnancy by use of a retrospective design},
url = {http://dx.doi.org/10.1093/aje/kwi172},
volume = {162},
year = {2005}
}