@article{Fuster2008,
author = {Fuster, Vicente and Zuluaga, Pilar and Colantonio, Sonia and de Blas, Clemente},
title= {Factors Associated with Recent Increase of Multiple Births in Spain},
year = {2008},
doi = {10.1375/twin.11.1.70},
journal = {Twin Research and Human Genetics},
volume = {11},
number = {1},
pages = {70--76},
}