MGA represents the Map Grid of Australia. Most topographic map sheets are projected onto the Universal Transverse Mercator (UTM) coordinate system, which is called the MGA (or Australian Map Grid) in Australia, depending on the datum used.
White, A, Sparrow, B., Leitch, E., Foulkes, J., Flitton, R., Lowe, A.J., Caddy-Retalic, S. (2012). AusPlots Rangelands Survey Protocols Manual. Version 1.2.9 page 18. Terrestrial Ecosystem Research Network and The University of Adelaide Press. https://doi.org/10.25901/5f2ca309cc9c2
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