By Brett Arends
Dow Jones Columnist

The plunge in markets worldwide is starting to open up some bargains for long-term investors. As usual, you should ignore the panic around you and look for solid value. Don't worry what the other guy is doing: Worry about your own money.

I don't think stock markets overall are cheap yet, so I wouldn't be an indiscriminate buyer, even in this rout. But there are opportunities. If you stick to quality you should do well over time.

And if you want to get an extra 15% off the price of the shares you buy, take a look at some closed-end funds.

Closed-ends are regulated, professionally-managed mutual funds just like the Vanguard or Fidelity ones everyone knows about, but with one twist: Shares in closed-end funds trade on the stock market, like those in, say, Apple or Exxon.

What that means: You can sometimes buy shares for less than the value of the fund's underlying holdings. That's like buying $1 worth of investments for 85 cents.

There are examples right now:

BlackRock S&P Quality Rankings, which invests in blue chip stocks like ExxonMobil, AT&T and Royal Bank of Canada, was 14% below net asset value at Monday's close (net asset values are only calculated after the close each night).

Cohen & Steers Dividend Majors Fund, which owns real-estate companies and dividend stocks: 17%.

Clough Global Equity, run by veteran hedge fund manager Chuck Clough: 15%.

Royce Value Trust, a well-known conservative small cap equity fund: 17%.

BlackRock Strategic Dividend Achievers Trust: 14%.

Some of these now offer very fat dividend yields, though with closed-ends you need to be aware that the dividends do not always correspond simply to the yield on a regular stock-they can include capital gains and return of capital as well as income.

The yields on the Clough fund and both BlackRock funds are about 7%. The Cohen & Steers fund: 4.5%.

For those looking for an entry point into China's long-term story, the long-running and well-regarded Greater China Fund is at a 15% discount. (At certain points in the last few years, when the China fad has been at its hottest, the shares have actually traded for more than the net asset value.)

The Templeton Dragon Fund invests across the Asia-Pacific rim (excluding Japan). Right now: a 15% discount.

For understandable reasons, the Ibero-America Fund, formerly known as the Spain Fund, is on sale: a 14% discount. Ditto the Thai Fund, with a 19% discount.

Maury Fertig, a closed-end fund expert, names two he likes especially: Legg Mason's LMP Capital & Income Fund, and NFJ Dividend, Interest and Premium Strategy.

The first is a balanced fund investing in dividend stocks and high quality bonds, he says. At Monday's close, the shares were selling for 18% below the net asset value. Tuesday morning they were down another 31 cents to $9.52. The distribution yield on the shares is 4.9%, according to the Closed-End Fund Association.

The second fund, NFJ, is a "covered call" fund. That means it uses a strategy of owning shares and then generating surplus income by selling call options against them. This is far less "risky" or exotic than it may at first sound: Studies have suggested that over the long term this can produce returns comparable to those on shares with less volatility.

At Monday's close shares in NFJ were selling for 17% below their net asset value, and Tuesday morning they were down another 25 cents to $13.70.

Fertig is the chief investment officer of Relative Value Partners, an investment firm in Northbrook, Ill., focused on wealthy clients.

When shopping for closed-ends, he says, investors should look for good discounts and concentrate on funds run by reputable firms. They should also check the long-term performance of the underlying net asset value, which tells you whether the managers know how to invest well.

And be aware that trading in closed-end funds is sometimes thin. That means you may not find it as easy to sell-for example in a fire sale like now-as you would with, say, a big exchange-traded fund. It also means you should be wary of placing a "market" order when buying or selling a fund. Set a price limit, so you don't end up accidentally buying for too much or selling for too little.

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