JSON Evidence for full_abstract1.json having null and blank citation.id fields.

full_abstract1.json

[
    {
        "evidence": {
            "bel_statement": "a(CHEBI:\"phorbol 13-acetate 12-myristate\") -> kin(p(HGNC:MAPK1))",
            "citation": {
                "type": "PubMed",
                "name": "J Biol Chem. 1997 Jul 4;272(27):16917-23.",
                "id": null,
                "date": null,
                "authors": null,
                "comment": null
            },
            "summary_text": "Phorbol ester tumor promoters, such as phorbol\\n12-myristate 13-acetate (PMA), are potent activators of\\nextracellular signal-regulated kinase 2 (ERK2), stress-activated\\nprotein kinase (SAPK), and p38 mitogen-activated protein kinase\\n(MAPK) in U937 human leukemic cells.",
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                    "name": "CellLine",
                    "value": "U-937"
                },
                {
                    "name": "Species",
                    "value": "9606"
                }
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                        "keyword": "CHEBI",
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                        "uri": "http://resource.belframework.org/belframework/20150611/namespace/hgnc-human-genes.belns"
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                        "keyword": "SCOMP",
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            "metadata": [
                {
                    "name": "document_header",
                    "value": {
                        "Name": "BEL Framework Example 1 Document",
                        "Description": "Example of modeling a full abstract taken from the BEL V1.0 Language Overview. ",
                        "Version": "20150611",
                        "Copyright": "Copyright (c) 2011-2015, Selventa. All Rights Reserved.",
                        "ContactInfo": "support@belframework.org",
                        "Authors": [
                            "Selventa"
                        ],
                        "Licenses": [
                            "Creative Commons Attribution-Non-Commercial-ShareAlike 3.0 Unported License"
                        ]
                    }
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        "evidence": {
            "bel_statement": "a(CHEBI:\"phorbol 13-acetate 12-myristate\") -> kin(p(HGNC:MAPK8))",
            "citation": {
                "type": "PubMed",
                "name": "J Biol Chem. 1997 Jul 4;272(27):16917-23.",
                "id": "",
                "date": null,
                "authors": null,
                "comment": null
            },
            "summary_text": "Phorbol ester tumor promoters, such as phorbol\\n12-myristate 13-acetate (PMA), are potent activators of\\nextracellular signal-regulated kinase 2 (ERK2), stress-activated\\nprotein kinase (SAPK), and p38 mitogen-activated protein kinase\\n(MAPK) in U937 human leukemic cells.",
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                    "name": "CellLine",
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                    "name": "document_header",
                    "value": {
                        "Name": "BEL Framework Example 1 Document",
                        "Description": "Example of modeling a full abstract taken from the BEL V1.0 Language Overview. ",
                        "Version": "20150611",
                        "Copyright": "Copyright (c) 2011-2015, Selventa. All Rights Reserved.",
                        "ContactInfo": "support@belframework.org",
                        "Authors": [
                            "Selventa"
                        ],
                        "Licenses": [
                            "Creative Commons Attribution-Non-Commercial-ShareAlike 3.0 Unported License"
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]