↑ Weights and Measures Act 1985, as amended; Schedule 1,Part VI, Definitions of certain units which may not be used for trade except as supplementary indications.
↑ NIST Special Publication 811, Guide for the Use of the International System of Units (SI), Appendix B, B.6, U.S. survey foot and mile. National Institute for Standards and Technology, U.S. Department of Commerce, 2008.
