Incumbent diagnostic companies will also express doubt since profit margins are thin.

After his release in 1988, he vigorously attempted to clear his name, and commentators continued to express doubt about the extent of his guilt.

He was the first mathematician to express doubt on non-constructive existence proofs.

This lack of accessibility, and questions about the account as a whole, has led foreign scholars to express doubt about the veracity of the claim.

It has declined public comment, but curators privately expressed doubts.