In the Name of Allah, the Inspirer of Truth.
Assalamu Alaikum Warahmatullahi Wabarakatuh

As long as the wording (written or verbal) constitutes a clear (sareeh) divorce, like "I hereby divorce my wife" or words to the effect, then divorce has fallen. Three talaaqs in one sitting though reprehensible, nevertheless all three will become effective. However, please note that giving three divorces in one sitting verbally or in writing, is prohibited in Shari'ah. If there is no chance of reconciliation, issue one divorce in writing to your wife in an amicable manner.

It is reported from Mahmood Ibn Labid that Rasulullah (Sallallaahu Alayhi Wasallam) was informed of a person who had given his wife three divorces at
once. Rasulullah (Sallallaahu Alayhi Wasallam) stood up in the state of anger and said, 'Are you playing with the Aayats of Allah and His Kitaab
whilst I am among you.' A person stood up and said, 'Oh Rasulullah! Should I not kill him?' (Mishkaat Vol2 p.284)

Three Talaaqs in one sitting
http://www.jamiat.org.za/ttalaaqs.html

With reference to the Canadian law, as long as it constitutes a valid, written divorce, it will become effective. However, consult with the
Jamiat-ul-Ulama Canada for more advice on Canadian Law. www.jucanada.org

And Allah knows Best
Wa Alaykumussalaam Wa Rahmatullahi Wa Barakatuh
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