GR96(1996) - EPSG:10956

WKT

GEOGCS["GR96(1996)", 
	DATUM["Greenland_Reference_1996_(1996)", 
		SPHEROID["GRS_1980", 6378137.0, 298.257222101]], 
	PRIMEM["Greenwich", 0.0], 
	UNIT["Degree", 0.0174532925199433]]

WKT2

GEOGCRS["GR96(1996)", 
	DATUM["Greenland_Reference_1996_(1996)", 
		ELLIPSOID["GRS_1980", 6378137.0, 298.257222101], 
		ANCHOREPOCH[1996.62]], 
	PRIMEM["Greenwich", 0.0], 
	CS[ellipsoidal, 2], 
	AXIS["Latitude (lat)", north, 
		ORDER[1]], 
	AXIS["Longitude (lon)", east, 
		ORDER[2]], 
	ANGLEUNIT["Degree", 0.0174532925199433], 
	ID["EPSG", "10956"]]

Data from @esri/proj-codes

{
  "wkid": 10956,
  "latestWkid": 10956,
  "macro": "PE_GCS_GR96_1996",
  "name": "GR96(1996)",
  "wkt": "GEOGCS[\"GR96(1996)\",DATUM[\"Greenland_Reference_1996_(1996)\",SPHEROID[\"GRS_1980\",6378137.0,298.257222101]],PRIMEM[\"Greenwich\",0.0],UNIT[\"Degree\",0.0174532925199433]]",
  "wkt2": "GEOGCRS[\"GR96(1996)\",DATUM[\"Greenland_Reference_1996_(1996)\",ELLIPSOID[\"GRS_1980\",6378137.0,298.257222101],ANCHOREPOCH[1996.62]],PRIMEM[\"Greenwich\",0.0],CS[ellipsoidal,2],AXIS[\"Latitude (lat)\",north,ORDER[1]],AXIS[\"Longitude (lon)\",east,ORDER[2]],ANGLEUNIT[\"Degree\",0.0174532925199433],ID[\"EPSG\",\"10956\"]]",
  "description": "GR96(1996)",
  "authority": "EPSG",
  "version": "12.016(13.6.0)",
  "deprecated": "no",
  "areaname": "Greenland",
  "extent": {
    "slat": 56.38,
    "nlat": 87.02,
    "llon": -75,
    "rlon": 7.99
  }
}