Table 1

Used abbreviations.

TMzn Transverse Mercator (map projection) for a fixed zone
LAEA Lambert Azimuthal Equal-Area (map projection)
LCC Lambert Conformal Conic (map projection)
GRS80 Geodetic Reference System (1980)
ETRS89 European Terrestrial Reference System (1989)
PT-TM06 ETRS89 datum for mainland Portugal based on TMzn (2006)
OAM Portugal Official Administrative Map of mainland Portugal (2016)
OAM Algarve Official Administrative Map of the Algarve (2016)
Geodetic Algarve Geodetic network of the Algarve (2016)
NAM Algarve New Administrative Map of the Algarve (2016)

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