Look up a non-US stock price

I need to get historical prices of certain non-US stocks (specifically, they are traded at Prague Stock Exchange, Czech Republic) but I am not able to find the proper "name" that Mathematica would accept. For example, is there a way to look up the Mathematica name for a stock if I know the ISIN code or the exchange (but probably not the exchange's Mathematica symbol) where the stock is traded?

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FinancialData["^PSE", "Members"] indicates that stocks on the Prague Stock Exchange are not supported. You can try using Yahoo Finance instead. – Pickett Jun 10 '14 at 9:10