21 cm Kanone 39 gun
21 cm Kanone 39 gun is a siege artillery or rifled breech loader.
Overview
It is associated with Czechoslovakia. Catalogue entries for arms and armour state maker, marks, mechanism and, where relevant, licensing. VALÉORINE records this subject so that lots referring to it can be described consistently.
In detail
Czech siege artillery
Sources
Each source is named with the standing the house places on it, so the evidence can be weighed rather than taken on trust.
reference work · Reputable secondary · Wikipedia
“21 cm Kanone 39”, English Wikipedia, consulted as further reading
Consult the sourcereference work · Reputable secondary · Wikidata
Wikidata, structured authority record Q442097: 21 cm Kanone 39 gun
Consult the source