21.   Police, Bell Canada and Ontario Hydro investigators have failed to pinpoint the source of the trouble.

22.   Although Japanese authorities have not pinpointed a source of the outbreak, they suspect raw meat, cold noodles or tuna paste.

23.   Conventional testing failed to pinpoint the source of the problem, which Van Exel compared to a knuckle cracking.

24.   Environmental tests were completed at ABC headquarters to try to pinpoint the source, but it could be days before results are known.

25.   Glowaczewska said more testing would be required to pinpoint the source of the contamination.

26.   He said health authorities were continuing an investigation to pinpoint the source of infection.

27.   Officials have not pinpointed the source of the potentially fatal strain of E. coli, found in the feces and intestines of cattle.

28.   Previous searches, including expeditions in central Africa, have been unable to pinpoint the source.

29.   State Health Department officials were still trying to pinpoint the source of the bacteria today.

30.   The government decided to begin lifting the bans Tuesday, confident it had done enough to pinpoint the source and spread of dioxin-tainted feed.