1866 - 20c on 15c blue, Type II horseshoe overprin

 1866 - 20c on 15c blue, Type II horseshoe overprint with ‘XX’ dotted numeral cancellation, alongside the double-circle ‘POSTA MILITARE ITALIANA (N.20) 11 LUG. 66’ on the front, on cover addressed to Livorno (24). Cover mentioned on p. 212 of the book 1866. La terza Guerra d'Indipendenza. La Posta Militare Italiana, study by Carra-Carraro, 11 recorded documents. Manzoni certificate