Convention signed at Geneva on 22 August 1864

Baden, one of the signatory states, is missing from this list:

Der internationale Sanitäts-Vertrag wurde unterzeichnet
von Belgien, Dänemark, Spanien, Frankreich, Hessen-Darm-
statt, Italien, Niederlande, Portugal, Preussen, Württem-
berg und der Schweiz.

Diplomatic notes from Greece and Mexico on their non-participation in the Congress

The French text of the Convention was published in the Revue militaire suisse.

https://www.nb.admin.ch/content/snl/en/home/themes/history/150-years-of-the-first-geneva-convention/convention-signed-at-geneva-on-22-august-1864.html