1. Statistics Canada, Canadian Vital Statistics, Birth and Stillbirth Databases 3231 and 3234. CANSIM Tables number 102–4515: Live births and fetal deaths (stillbirths), by type (single or multiple), Canada, provinces and territories, annual (number).
http://estat.statcan.gc.ca/cgi-win/cnsmcgi.pgm?LANG=E&CIITables=3871&ResultTemplate=ESTAT\CII_FLST&ROOTDIR=ESTAT/&LangFldr=English/&C2DB=
. Table number 102–4515. Accessed in April 2013.
2. Statistics Canada: Births 2009. 2012, Ottawa: Minister of Industry, Catalogue no. 84F0210X.
http://www.statcan.gc.ca/pub/84f0210x/84f0210x2009000-eng.pdf
. Accessed in April 2013
3. Martin JA, Hamilton BE, Ventura SJ, Osterman MJK, Kirmeyer S, Mathews TJ, Wilson E: Births: Final data for. 2009,
http://www.cdc.gov/nchs/data/nvsr/nvsr60/nvsr60_01.pdf
Accessed: January 2012, . National Vital Statistics Reports 2011. Volume 60, Number 1
4. National Center for Health Statistics: Vital Statistics of the United States, 1980, Vol. 1, Natality. DHHS Pub. No. (PHS) 85–1100. Public Health Service. 1984, Washington. U.S: Government Printing Office,
http://www.cdc.gov/nchs/data/vsus/nat80_1acc.pdf
Accessed: January 2012
5. European Commision: Eurostat yearbook 2002; The statistical guide to Europe, Data 1990–2000. 2002, Luxembourg: Office for Official Publications of the European Communities, 30-
http://epp.eurostat.ec.europa.eu/cache/ITY_OFFPUB/KS-40-01-319/EN/KS-40-01-319-EN.PDF
Accessed: April 2013, 92-894-1750-1