The visa-office specific instructions for New Delhi provide the following instructions (p. A-4):
http://www.cic.gc.ca/english/information/applications/skilled-mission.asp
If you have experience as a self-employed person, provide copies of:
•business/company registration documents,
•proof of business conducted with clients (invoices, bills, client references)
•balance sheets,
•income tax returns, and/or
•proof of your licence to practice (if you are a private practitioner)