Format of basis set references

[bingao]

Dear all,

I am trying to obtain references for basis sets by using REST API. For example, https://www.basissetexchange.org/api/references/4-31g/format/json/?version=0 returns references for 4-31G (version 0):

[
    {
        "reference_info": [
            {
                "reference_description": "31G valence double-zeta",
                "reference_data": [
                    [
                        "ditchfield1971a",
                        {
                            "_entry_type": "article",
                            "authors": [
                                "Ditchfield, R.",
                                "Hehre, W. J.",
                                "Pople, J. A."
                            ],
                            "title": "Self-Consistent Molecular-Orbital Methods. IX. An Extended Gaussian-Type Basis for Molecular-Orbital Studies of Organic Molecules",
                            "journal": "J. Chem. Phys.",
                            "volume": "54",
                            "pages": "724-728",
                            "year": "1971",
                            "doi": "10.1063/1.1674902"
                        }
                    ]
                ]
            }
        ],
        "elements": [
            "1"
        ]
    },
    ...
]

My question is about the format/schema of the field reference_data. From the above example, the value of reference_data is an array. Elements of this array are also arrays. Is it correct that only reference's key (in this example, ditchfield1971a) and content are in these arrays?

Thank you.