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I can see you do not have the email field in your forms so far, if you're sending the email to each individual email address then you may add a hidden email field and pre-populate the field with the email address you're sending the form.
This is a sample link that you may use: http://firstname.lastname@example.org
And change the email address pre-populated in the link as you send it to each email address.
Another way would be to ask for the email address or other info in the form and set it as required, otherwise in the Form Analytics tool you will be able to get only the IP address where the form was submitted from as well as the device used.
Please if you have any question, let us know.