Small companies are the biggest post-coronavirus battleground on Wall Street. 4 of the world's best fund managers share their strategies for the space — and the single stocks they love.

· The stock market's smallest companies are facing unprecedented doubts and have taken huge losses as investors wonder about their ability to survive. 
· With that as a backdrop, Business Insider spoke to four of the most successful small-company fund managers in the world.
· All four discussed their investment strategies...