The topic has been the subject of religious debate and scientific investigation for more than a century.

He decided to turn his instinct into a scientific investigation.

In the 18th century, the differences among human groups became a focus of scientific investigation.

Only scientific investigation can show which is more likely to be correct.

The problem needed to be handed over to scientific investigation.

The first step in any good scientific investigation is a literature search.

Furthermore, he says that this is the case for almost all scientific investigation.

The woman is taken to France in 1814 and from then on became a subject of scientific investigation.

This might be the last scientific investigation permitted for a long time.

We based our decision on political ideology rather than scientific investigation.