The use of anonymous sources has been a controversial subject for many years.

The use of offshore sources for options is also popular.

Teachers from across the country attend and learn methods for the effective use of primary sources.

In particular, research into and the use of renewable energy sources must be promoted.

It is important to promote the use of renewable energy sources.

First, there is a need to restrict the use of anonymous sources, particularly for information that seems to be very important.

The use of alternative energy sources is the most logical answer to increasing oil prices.

We must also remember that the use of renewable energy sources has a positive effect on regional development and employment.

However, according to the majority view, the author is unknown, the author's use of varied sources telling against the traditional account.

That way the readers would know how often the Times's stringent criteria for the use of such sources are met.