NOI - Ontario: I need HOW many Employer referral letters??

[kmich]

Reading thru the SUPREMELY detailed thread located here, it mentions that i need referral letters from my employers covering the last 10 years (over 18). So even though I have over a year of work experience here in Canada, I still need the referral letters going back that far? What if I've worked for 5 different firms in that time frame? I can't imagine getting referral letters from them in time to submit for PNP.