A series of tests were carried out in 1880, to check their efficiency.
In the 1980s, a series of individual surveys on innovation was carried out.
Insurgents have carried out a series of other sophisticated attacks in recent days.
They were to carry out a series of investigations beginning today and ending on Thursday.
The scientists are carrying out an ambitious series of experiments to answer these questions.
A series of five operations were carried out over a period of two years.
Police are stepping up their hunt for a man who's carried out a series of sexual attacks on women in the last seven months.
He wants to carry out a series of tests.
Starting in 1952, a series of pilot renovations were carried out.
The whole series of operations were excellently conceived and carried out.