1.   Further, no firm experimental evidence shows that these drugs diminish regional cerebral blood flow in migraineurs.

2.   It was thought for a long time that he was a Carthusian but there is no firm evidence for this.

3.   There is no firm evidence either way.

4.   Yet dozens of independent scientists around the world have provided firm evidence linking OPs with similar symptoms.

5.   Despite claims about ancient astronauts and unidentified flying objects, there is no firm evidence for past visitations of the Earth by other civilization.

6.   All had probably served the Nevilles, although firm evidence survives only for the Withams, Gowers and Constables.

7.   Such examples could be taken to demonstrate the homogeneity of the ducal retinue, except that there is no firm evidence of movement in the opposite direction.

8.   Here is some firm evidence that climate plays an important part in determining the condition of our forests.

9.   And the administration points out that there is no firm evidence that the budget surplus is being diminished by the softer economy.