@article{e93f87bae0934cd2adf1312529ed279f,
title = "Units of analysis - Matched pairs, single patient, or cycles? [2] (multiple letters)",
author = "Whitcomb, {Brian W.} and Schisterman, {Enrique F.} and Garcia-Velasco, {Juan A.} and Aydin Arici and Antonio Pellicer",
year = "2004",
month = oct,
doi = "10.1016/j.fertnstert.2004.07.004",
language = "English (US)",
volume = "82",
pages = "987--988",
journal = "Fertility and sterility",
issn = "0015-0282",
publisher = "Elsevier Inc.",
number = "4",
}