An HDF5 Object Reference Datatype (Attribute)

{
    "apiVersion": "1.0.0",
    "datasets": {
        "a09a7f14-7bf7-11e4-8eef-3c15c2da029e": {
            "attributes": [
                {
                    "name": "A1", 
                    "shape": {
                        "class": "H5S_SIMPLE", 
                        "dims": [2]
                    }, 
                    "type": {
                        "base": "H5T_STD_REF_OBJ", 
                        "class": "H5T_REFERENCE"
                    }, 
                    "value": [
                        "groups/a09a9b99-7bf7-11e4-aa4b-3c15c2da029e", 
                        "datasets/a09a8efa-7bf7-11e4-9fb6-3c15c2da029e"
                    ]
                }
            ], 
            "shape": {
                "class": "H5S_NULL"
            }, 
            "type": {
                "base": "H5T_STD_I32LE", 
                "class": "H5T_INTEGER"
            }, 
            "value": null
        }, 
        "a09a8efa-7bf7-11e4-9fb6-3c15c2da029e": {
            "shape": {
                "class": "H5S_NULL"
            }, 
            "type": {
                "base": "H5T_STD_I32LE", 
                "class": "H5T_INTEGER"
            }, 
            "value": null
        }
    }, 
    "groups": {
        "a099880c-7bf7-11e4-82d6-3c15c2da029e": {
            "links": [
                {
		    "class": "H5L_TYPE_HARD",
                    "title": "DS1",
		    "collection": "datasets",
                    "id": "a09a7f14-7bf7-11e4-8eef-3c15c2da029e" 
                }, 
                {
		    "class": "H5L_TYPE_HARD",
                    "title": "DS2",
		    "collection": "datasets",
                    "id": "a09a8efa-7bf7-11e4-9fb6-3c15c2da029e"
                }, 
                {
		    "class": "H5L_TYPE_HARD",
                    "title": "G1",
		    "collection": "groups",
                    "id": "a09a9b99-7bf7-11e4-aa4b-3c15c2da029e"
                }
            ]
        }, 
        "a09a9b99-7bf7-11e4-aa4b-3c15c2da029e": {}
    }, 
    "root": "a099880c-7bf7-11e4-82d6-3c15c2da029e"
}