@article{doi:10.1001/jama.1989.03420160053017,
author = {Knoke JD and Sokol RJ},
title = {EStimates of gestational age},
journal = {JAMA},
volume = {261},
number = {16},
pages = {2329},
year = {1989},
doi = {10.1001/jama.1989.03420160053017},
URL = { + http://dx.doi.org/10.1001/jama.1989.03420160053017},
eprint = {/data/Journals/JAMA/9159/jama_261_16_017.pdf}
}