APA

Colley Gilbert B. J., Johnson C. H., Morrow B., Gaffield M. E. & Ahluwalia I. (19991005). Prevalence of selected maternal and infant characteristics, Pregnancy Risk Assessment Monitoring System (PRAMS), 1997. : MMWR. CDC surveillance summaries : Morbidity and mortality weekly report. CDC surveillance summaries.

Chicago

Colley Gilbert B J, Johnson C H, Morrow B, Gaffield M E and Ahluwalia I. 19991005. Prevalence of selected maternal and infant characteristics, Pregnancy Risk Assessment Monitoring System (PRAMS), 1997. : MMWR. CDC surveillance summaries : Morbidity and mortality weekly report. CDC surveillance summaries.

Harvard

Colley Gilbert B. J., Johnson C. H., Morrow B., Gaffield M. E. and Ahluwalia I. (19991005). Prevalence of selected maternal and infant characteristics, Pregnancy Risk Assessment Monitoring System (PRAMS), 1997. : MMWR. CDC surveillance summaries : Morbidity and mortality weekly report. CDC surveillance summaries.

MLA

Colley Gilbert B J, Johnson C H, Morrow B, Gaffield M E and Ahluwalia I. Prevalence of selected maternal and infant characteristics, Pregnancy Risk Assessment Monitoring System (PRAMS), 1997. : MMWR. CDC surveillance summaries : Morbidity and mortality weekly report. CDC surveillance summaries. 19991005.