AFAIK, the GM does not belong to any reigning royal family. You said it is included in the GHdA. I did not say the opposite. But it is not listed in the section I of the Almanach de Gotha. The prestige and authority of the latter cannot be compared to the former.
When Manuel refers to the Almanach de Gotha, I am not sure whether he means the Justus Perthes publication which ceased in 1944 or the London publication which began in 1998.
The Perthes publication certainly had prestige and authority, but is Manuel suggesting that a similar prestige and authority, greater than the GHdA, is attached to the London publication? Certainly the London publication has been widely criticised.
Since the Perthes Almanach de Gotha ceased publication in 1944, it is the GHdA which has become the leading print publication in the area.
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