Citizenship Act (Canada)
https://laws-lois.justice.gc.ca/eng/acts/C-29/

Changes to citizenship rules 2009 to 2015
https://www.canada.ca/en/immigration-refugees-citizenship/services/canadian-citizenship/act-changes/rules-2009-2015.html

Immigration and citizenship
https://www.canada.ca/en//immigration-citizenship.html

Canadian Citizenship
https://www.canada.ca/en/immigration-refugees-citizenship/services/canadian-citizenship.html

Immigration, Refugees, and Citizenship Canada (IRCC)
https://www.canada.ca/en/immigration-refugees-citizenship.html

See if you may be a citizen
https://www.canada.ca/en/immigration-refugees-citizenship/services/canadian-citizenship/become-canadian-citizen/eligibility/already-citizen.html

Resume Canadian citizenship: About the process
https://www.canada.ca/en/immigration-refugees-citizenship/services/canadian-citizenship/resume-canadian-citizenship.html

Get proof of citizenship
https://www.canada.ca/en/immigration-refugees-citizenship/services/canadian-citizenship/proof-citizenship.html

Give up (renounce) Canadian citizenship: About the process
https://www.canada.ca/en/immigration-refugees-citizenship/services/canadian-citizenship/renounce-canadian-citizenship.html

Visitor Visa Eligibility Requirements
https://www.canada.ca/en/immigration-refugees-citizenship/services/visit-canada/eligibility.html

Entry Requirements
https://www.canada.ca/en/immigration-refugees-citizenship/services/visit-canada/entry-requirements-country.html

How long can I stay in Canada as a visitor?
https://www.cic.gc.ca/english/helpcentre/answer.asp?qnum=1016&top=16