@inbook{Fretts2008,
author = {Fretts, R.C. and Zera, C. and Heffner, L.J.},
title= {Maternal age and pregnancy},
year = {2008},
doi = {10.1016/B978-012370877-9.00097-9},
editor = {Haith, M.M.},
editor = {Benson, J.B.},
booktitle = {Encyclopedia of infant and early childhood development},
address = {Amsterdam},
publisher = {Elsevier, Academic Press},
pages = {259--267},
}