The basics about powershares qqq and other liquid funds of this etf company.
Technical support & resistance levels in Nasdaq & S&P 500
Time-frame selection for qqq day trading systems - Simple stock trading
Powershares QQQ ETF - Simple stock trading
Exchange Traded Fund (ETF) - What are ETFs and Why to Invest?
Six exchange-traded funds (ETFs) that track the major indexes
Why is the QQQ ETF outperforming the PNQI ETF? They are both meant to track big tech companies. - Quora
Comparison Of Qqq With Other Technology Etfs - FasterCapital
PowerShares QQQ Is Ending May in a Popping Bubble - TheStreet
Trade of the Day: Nasdaq 100 QQQ ETF in Risky Territory
Major Nasdaq ETF symbols - Simple stock trading