A method of imputing length of gestation on birth certificates /
Taffel, Selma.
Johnson, David P.
Heuser, Robert L.
Hyattsville, Md. : U.S. Dept. of Health and Human Services, Public Health Services, Office of Health Research, Statistics, and Technology, National Center for Health Statistics ,
1982.
Includes bibliographical references.
Conception
Pregnancy
Pregnancy