"Exercise,diet,cognitive stimulation showed some positive effects, although the evidence was not so strong that we could actually consider these firmly established."

VOA: standard.2010.06.17

People have argued over the authenticity of them, although I think by now it is established that they are his.

虽然人们曾质疑其真假，但我想现在应该尘埃落定,确定是他亲笔所写。

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