Question: What is the country code that, along with no and sj is domain name registry for the three Norwegian country not open for?
Context: A country code second-level domain is a second-level domain to a country code top-level domain.  Such a domain may be reserved by the domain name registry for the registration of third-level domains or assigned to a third party as a subdomain. . bv is the Internet country code top-level domain (ccTLD) reserved for the uninhabited Norwegian dependent territory of Bouvet Island.  The domain name registry and sponsor is Norid, but . bv is not open for registration.  . bv was designated on 21 August 1997 and was placed under the . no registry Norid.  Norwegian policy states that . no is sufficient for those institutions connected to Bouvet Island, and therefore the domain is not open to registration.  It is Norwegian policy not to commercialize domain resources, so there are no plans to sell . bv .  Should the domain later come into use, it will be under the regulation of the Norwegian Post and Telecommunications Authority and follow the same policy as . no . The domain name . рф (romanized as . rf; abbreviation of Russian: Росси́йская Федера́ция , "Rossijskaja Federacija") is the Cyrillic country code top-level domain for the Russian Federation, in the Domain Name System of the Internet.  In the Domain Name System it has the ASCII DNS name xn--p1ai .  The domain accepts only Cyrillic subdomain applications, and is the first Cyrillic implementation of the Internationalizing Domain Names in Applications (IDNA) system.  The domain became operational on 13 May 2010.  As of 2014 it is the most used internationalized country code top-level domain, with around 900,000 domain names. . rs is the Internet country code top-level domain (ccTLD) for Serbia.  The domain name registry that operates it is the Serbian National Internet Domain Registry (RNIDS).  The letters "rs" stand for "Republika Srbija "/Република Србија (Republic of Serbia). Uninett Norid AS, trading as Norid, is the domain name registry for the three Norwegian country code top-level domains (ccTLD) . no, . sj and . bv.  The non-profit company is based in Trondheim, where it shares offices with its parent company Uninett; both companies being owned by the Norwegian Ministry of Education and Research.  Norid operates under contract with the Internet Assigned Numbers Authority, supervised by the Norwegian Post and Telecommunications Authority.  Uninett took over responsibility for the Norwegian domain in 1987, and in 2003 it was spun off as a separate company.  Only . no is open for registration. The IE Domain Registry (IEDR) is the domain name registry for the . ie country code top-level domain.  Formally, the "IE Domain Registry Limited" is a private company, limited by guarantee, incorporated in Ireland having its registered office and principal place of business in Dún Laoghaire, County Dublin.  It operates on a not-for-profit basis and is a member of the CENTR representative body.  "IE Domain Registry Limited" took over the administration of . ie in July 2000.  Prior to that, the . ie ccTLD had been administered by University College Dublin. . sj is the Internet country code top-level domain (ccTLD) reserved for the designation Svalbard and Jan Mayen.  The domain name registry is Norid, but . sj is not open for registration.  The issuing of the domain was based on the ISO 3166 designation of Svalbard and Jan Mayen, which consists of two separately administrated integrated territories of Norway: the Arctic archipelago Svalbard and the nearly uninhabited volcanic island Jan Mayen.  . sj was designated on 21 August 1997, at the same time as Bouvet Island was allocated . bv .  Both were placed under the . no registry Norid, which is also the sponsor.  Norwegian policy states that . no is sufficient for those institutions connected to both Svalbard and Jan Mayen, and therefore the domain is not open to registration.  It is Norwegian policy not to commercialize domain resources, so there are no plans to sell . sj .  Should the domain later come into use, it will be under regulation of the Norwegian Post and Telecommunications Authority and follow the same policy as . no .  There are two second-level domains reserved for the two areas: svalbard.no and jan-mayen. no , but other web addresses are also used. A domain name registrar is an organization or commercial entity that manages the reservation of internet domain names.  A domain name registrar must be accredited by a generic top-level domain (gTLD) registry and/or a country code top-level domain (ccTLD) registry.  The management is done in accordance with the guidelines of the designated domain name registries. . no is the Internet country code top-level domain (ccTLD) for Norway.  Norid, the domain name registry, is based in Trondheim, is owned by the state-owned Uninett and operates under supervision of the Norwegian Post and Telecommunications Authority.  As of May 10, 2013 there were 583,962 registered . no -domains.  Organizations with a presence in Norway and registration at the Brønnøysund Register Centre are limited to 100 domains each.  Individuals residing in Norway may register in the second-level domain priv.no and, as of June 17, 2014, directly under . no .  Other second-level domains exist for organizations of certain types, such as municipalities and schools.  The strict regulations have resulted in near-absence of cybersquatting and warehousing. A drop registrar is a domain name registrar who registers expiring Internet domain names immediately after they expire and are deleted by the domain name registry.  A drop registrar will typically use automated software to send up to 250 simultaneous domain name registration requests in an attempt to register the domain name first.  In recognition of the potential abuse of such a "domain land rush", ICANN and VeriSign limited the number of simultaneous requests to 250 since July 17, 2001.
Answer: registration