Am 16.04.2018 um 18:07 schrieb Riccardo (Jack) Lucchetti:
 Hm, I see. I personally would prefer redefining the $\Gamma$
matrices.  
Fine with me. Only that the sentence "... expresses \Sigma as the 
long-run covariance of..." would also have to be adapted with a phrase 
like "proportional to" or something.
-sven