If you are not a Canadian citizen you will need the L-2 visa. Other than that a copy of your spouses L-1 visa and I-94 card or printout from cup website. A copy of I -797 is fine with the other documents. Marriage certificate would be helpful also. A copy of your husbands recent pay statement and a letter for his employer would be helpful. This may be overkill bit why take a chance is my philosophy. Good luck.
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