APA
Frank R., Jackson Ca, Salkever Ds & Strobino Dm. (1991). Updated Estimates Of The Impact Of Prenatal Care On Birthweight Outcomes By Race. Cambridge, MA: NBER.
Chicago
Frank RG, Jackson Ca, Salkever Ds and Strobino Dm. 1991. Updated Estimates Of The Impact Of Prenatal Care On Birthweight Outcomes By Race. Cambridge, MA: NBER.
Harvard
Frank R., Jackson Ca, Salkever Ds and Strobino Dm. (1991). Updated Estimates Of The Impact Of Prenatal Care On Birthweight Outcomes By Race. Cambridge, MA: NBER.
MLA
Frank RG, Jackson Ca, Salkever Ds and Strobino Dm. Updated Estimates Of The Impact Of Prenatal Care On Birthweight Outcomes By Race. Cambridge, MA: NBER. 1991.