No research or studies required - it's all there already.

The study of these waves requires very large radio telescopes.

Another study on an antibiotic required that patients have a certain type of bacteria growing in their ear.

The study of demands on the operator requires task analysis.

Human studies required a better source of the radioactive Iodine.

The study of sculpture requires good technical skills and theoretical knowledge on the student's part.

A new study required that its subjects have actual sexual experience with both men and women.

He said such a study would require more than 100,000 women under the age of 40.

The Swedish studies are the heart of the current debate and will require further analysis by other expert groups.

A historical study may require documentary and statistical evidence to test out a number of hypotheses.