From https://en.wikipedia.org/wiki/The_Superinvestors_of_Graham-a... :
> The speech and article challenged the idea that equity markets are efficient through a study of nine successful investment funds generating long-term returns above the market index.
From https://en.wikipedia.org/wiki/The_Superinvestors_of_Graham-a... :
> The speech and article challenged the idea that equity markets are efficient through a study of nine successful investment funds generating long-term returns above the market index.