The Constitution of the German Empire (April 16, 1871)
Here we see a facsimile of the first page of the Reichstag law of April 16, 1871, which proclaimed a new constitution for the German Empire.
Source: Bundes-Gesetzblatt des Deutschen Bundes (Berlin), no. 16 ( April 20, 1871). Reproduced in Elmar M Hucko, Von der Paulskirche zum Museum Koenig: The Democratic Tradition: Four German Constitutions. Leamington Spa, NY: Berg, 1987, p. 119.