Name	Info	Provider	Link
	free resource	Elsevier Science	https://linkinghub.elsevier.com/retrieve/pii/0091-2182(89)90081-5
Childbirth	free resource	MedlinePlus Health Information	https://medlineplus.gov/childbirth.html
	subscription/membership/fee required	Wiley	https://onlinelibrary.wiley.com/resolve/openurl?genre=article&sid=nlm:pubmed&issn=0091-2182&date=1989&volume=34&issue=4&spage=193