As yet these claims are unsubstantiated.
When it comes to memory and supplements there's a wide range of choices, but do your research before taking any supplement for memory because many of the claims made are unsubstantiated.
While some of these theories are entirely unsubstantiated, many of them are backed up by historical fact and thus are considered reasonable possibilities by historians.
The pope was accused of having exaggerated the conspiracy of the cardinals for purposes of financial gain, but most of such accusations appear to be unsubstantiated.
A judge agreed with a defense attorney that the police had no probable cause for a search based solely on an unsubstantiated tip.