Finance Canada (for tax treaties in force)
- https://www.fin.gc.ca/treaties-conventions/in_force--eng.asp
Internal Revenue Service (IRS)
- http://www.irs.gov
American Chamber of Commerce in Canada
- http://www.amchamcanada.ca
Export Québec
- http://www.export.gouv.qc.ca/accueil-export-quebec/
