WGS 1966 - ESRI:37001

WKT

GEOGCS["GCS_WGS_1966", 
	DATUM["D_WGS_1966", 
		SPHEROID["NWL_9D", 6378145.0, 298.25]], 
	PRIMEM["Greenwich", 0.0], 
	UNIT["Degree", 0.0174532925199433]]

WKT2

GEOGCRS["GCS_WGS_1966", 
	DYNAMIC[
		FRAMEEPOCH[1966.0]], 
	DATUM["D_WGS_1966", 
		ELLIPSOID["NWL_9D", 6378145.0, 298.25]], 
	PRIMEM["Greenwich", 0.0], 
	CS[ellipsoidal, 2], 
	AXIS["Latitude (lat)", north, 
		ORDER[1]], 
	AXIS["Longitude (lon)", east, 
		ORDER[2]], 
	ANGLEUNIT["Degree", 0.0174532925199433], 
	ID["Esri", "4760"]]

Data from @esri/proj-codes

{
  "wkid": 37001,
  "latestWkid": 4760,
  "macro": "PE_GCS_WGS_1966",
  "name": "GCS_WGS_1966",
  "wkt": "GEOGCS[\"GCS_WGS_1966\",DATUM[\"D_WGS_1966\",SPHEROID[\"NWL_9D\",6378145.0,298.25]],PRIMEM[\"Greenwich\",0.0],UNIT[\"Degree\",0.0174532925199433]]",
  "wkt2": "GEOGCRS[\"GCS_WGS_1966\",DYNAMIC[FRAMEEPOCH[1966.0]],DATUM[\"D_WGS_1966\",ELLIPSOID[\"NWL_9D\",6378145.0,298.25]],PRIMEM[\"Greenwich\",0.0],CS[ellipsoidal,2],AXIS[\"Latitude (lat)\",north,ORDER[1]],AXIS[\"Longitude (lon)\",east,ORDER[2]],ANGLEUNIT[\"Degree\",0.0174532925199433],ID[\"Esri\",\"4760\"]]",
  "description": "WGS 1966",
  "authority": "Esri",
  "version": "4.0.0",
  "deprecated": "codechange",
  "areaname": "World",
  "extent": {
    "slat": -90,
    "nlat": 90,
    "llon": -180,
    "rlon": 180
  },
  "frameEpoch": 1966,
  "deformationModel": ""
}