Native english article writer for long term needs

I need experienced article writers for long term, i will need more then 1000 articles/month. Need native english writers and i can accept writers from asian countries too if they have got good feedback and have amazing english skills. I need article writer for long term so prices should be reasonable. Writers should do full research before writing articles. Please places bids for 500 articles/month. I will need 1000+ articles if i like the work.