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A citizen of Argentina would ordinarily need a transit visa, even for a short layover.
However, US permanent residents with valid green cards do not need a visa, but only an eTA (Electronic Travel Authorization) to enter by air. You can apply for one online, and usually get an answer within minutes. When you fill out the eTA application, you'll be asked if you're a US permanent resident, and if you answer yes, you'll be asked to supply the details from your green card.
Be sure to carry your green card with you when you travel.