r further details on country code history and development, see History of Country Codes (WTNG).See also[සංස්කරණය]E.164International Telecommunication UnionList of international call prefixesInternational mobile phone codesTelephone numbering planGroup identifiers in ISBNs, a similar form of country codeLocal conventions for writing telephone numbersReferences[සංස්කරණය]↑ not yet implemented↑ 2.0 2.1 2.2 2.3 Sint Maarten will join the North American Numbering Plan on 30 September 2011, at which time it will adopt dialing code +1 721.[4]↑ "European Telephony Numbering Space (ETNS)". 28 මැයි 2009. සම්ප්‍රවේශය 20 ඔක්තෝබර් 2010.↑ "PL-423: Updated Information -  Introduction of NPA 721 (Sint Maarten)" (PDF). North American Numbering Plan Administration. 27 ජූලි 2011. සම්ප්‍රවේශය 29 ජූලි 2011.↑ 5.0 5.1 "Abkhazia remains available by Georgian phone codes". Today.Az. 6 ජනවාරි 2010. සම්ප්‍රවේශය 20 ජනවාරි 2010.↑ GNCC Communication of 30.III.2010[permanent dead link]↑ 7.0 7