+1(514) 937-9445 or Toll-free (Canada & US) +1 (888) 947-9445
This was my list -

BLS appointment letter (hard copy or soft copy to show at door)
Online application form printout
Surrender Certificate
Surrendered i.e., last held Indian passport (front & back pages)
Citizenship certificate
Canadian passport
Professional Details - I used employment confirmation letter which contained my start date with the employer and job title
eCOPR
Voter/Ration card Declaration
Address proof
Spouse's current passport - my application was on basis of my Indian origin only, but I provided this as my current marital status is not updated on my surrendered Indian passport, plus I got married in Canada
Registered marriage certificate - for same reason as above

Hi. How do you get a voter/ration card? I've registered on the Elections Canada website but dont have the card. Will I still be able to apply for OCI?
 
Hi. How do you get a voter/ration card? I've registered on the Elections Canada website but dont have the card. Will I still be able to apply for OCI?
Wow - wonderful question, maybe canada will issue ration card in another 100 years, do you need OCI immediately or can you wait a little
 
Hi. How do you get a voter/ration card? I've registered on the Elections Canada website but dont have the card. Will I still be able to apply for OCI?
This is Voter ID/Ration Card issued by Government in India i.e. Indian Authorities. You need a Declaration form signed with the application