11.   Lou Marcoccio, managing partner of the Gartner Group, an internationally known consulting group, said some of these measures may be unnecessary.

12.   One report said the Islamic Jihad took responsibility while another report cited a lesser known group called Palestinian Hezbollah.

13.   The letters contained no obvious messages from known militant groups.

14.   The studies were done by comparing the skull size of Kennewick Man with that of all the known ethnic groups.

15.   The Turkana people of Kenya show the greatest diversity of any known group in their mitochondrial DNA, said Dr. Elizabeth Watson, of Massey University in New Zealand.

16.   They say that there are few phone or other communications records showing that the four known hijacking groups communicated with each other.

17.   To keep himself fluid, Rivera practices with The Floor Lords, a nationally known group that has been featured in The Source, a hip-hop magazine.

18.   Police used sticks to battle the Germans, who reportedly included known groups of neo-Nazis who had arrived by train.

19.   A little known underground group calling itself Black Mamba, after a venomous snake, claimed responsibility for the first three sabotage attempts.

20.   A little known group calling itself Al Faran claimed responsibility when the four men disappeared.