Description: English: A Vipera kaznakovi, in Viperidae. Date: 17 March 2009. Source: Own work. Author: Mitternacht90. Permission(Reusing this file): PD. Taken at the OKC Zoo. Licensing[edit] Public domainPublic domainfalsefalse. : I, the copyright holder of this work, release this work into the public domain. This applies worldwide.In some countries this may not be legally possible; if so:I grant anyone the right to use this work for any purpose, without any conditions, unless such conditions are required by law.