S34S-IRF - EPSG:10249

WKT

GEOGCS["S34S-IRF", 
	DATUM["System_34_Sjaelland_Intermediate_Datum", 
		SPHEROID["International_1924", 6378388.0, 297.0]], 
	PRIMEM["Greenwich", 0.0], 
	UNIT["Degree", 0.0174532925199433]]

WKT2

GEOGCRS["S34S-IRF", 
	DATUM["System_34_Sjaelland_Intermediate_Datum", 
		ELLIPSOID["International_1924", 6378388.0, 297.0]], 
	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", "10249"]]

Data from @esri/proj-codes

{
  "wkid": 10249,
  "latestWkid": 10249,
  "macro": "PE_GCS_S34S_IRF",
  "name": "S34S-IRF",
  "wkt": "GEOGCS[\"S34S-IRF\",DATUM[\"System_34_Sjaelland_Intermediate_Datum\",SPHEROID[\"International_1924\",6378388.0,297.0]],PRIMEM[\"Greenwich\",0.0],UNIT[\"Degree\",0.0174532925199433]]",
  "wkt2": "GEOGCRS[\"S34S-IRF\",DATUM[\"System_34_Sjaelland_Intermediate_Datum\",ELLIPSOID[\"International_1924\",6378388.0,297.0]],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\",\"10249\"]]",
  "description": "S34S-IRF",
  "authority": "EPSG",
  "version": "10.088(13.2.0)",
  "deprecated": "no",
  "areaname": "Denmark - onshore Zealand and Lolland",
  "extent": {
    "slat": 54.51,
    "nlat": 56.79,
    "llon": 10.79,
    "rlon": 12.87
  }
}