A large-scale investigation was carried out but no trace of the boy has ever been found.

The Times inquiry has already resulted in a large-scale criminal investigation.

The expedition was widely publicized, and this second large-scale investigation led to further discussions of opening the site up to tourism.

"We don't have the means at our disposal for a large-scale investigation."

It is the first large-scale statistical investigation of gambling and suicide.

Mr. Romley said the two cases brought last week were just the beginning of a large-scale investigation involving several lawyers and investigators in his office.

The polygraph investigation was part of a large-scale investigation into intelligence leaks.

A number of large-scale investigations about language learning and the increased emphasis on reading skills in the 1920s led to the notion of "vocabulary control".

In 1914, he began the first large-scale investigations of the new sewage treatment process called activated sludge.

With her brother, she carried out a large-scale investigation into poverty in the city.