A guide to coordinate systems in Great Britain. This is available as a pdf document at
["Archived copy". Arquivado dende o orixinal o 11 de febreiro de 2012. Consultado o 2012-01-11.]] Appendices B1, B2
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A guide to coordinate systems in Great Britain. This is available as a pdf document at
["Archived copy". Arquivado dende o orixinal o 11 de febreiro de 2012. Consultado o 2012-01-11.]] Appendices B1, B2