I have a biomart xml query and I am going to obtain the data with curl and the RESTfull de biomart.

In the dataset it is defined the specie and ensembl but not the version of ensembl to use.​

    <?xml version="1.0" encoding="UTF-8"?>
    <!DOCTYPE Query>
    <Query virtualSchemaName = "default" formatter = "TSV" header = "0" uniqueRows = "0" count = "" datasetConfigVersion = "0.6" >
    
    <Dataset name = "hsapiens_gene_ensembl" interface = "default" >
        <Filter name = "hgnc_symbol" value = "LDLR"/>
        <Attribute name = "external_gene_db" />
        <Attribute name = "ensembl_gene_id" />
        <Attribute name = "chromosome_name" />
        <Attribute name = "start_position" />
        <Attribute name = "end_position" />
        <Attribute name = "strand" />
        <Attribute name = "ensembl_transcript_id" />
        <Attribute name = "ensembl_exon_id" />
        <Attribute name = "rank" />
        <Attribute name = "exon_chrom_start" />
        <Attribute name = "exon_chrom_end" />
        <Attribute name = "genomic_coding_start" />
        <Attribute name = "genomic_coding_end" />
    </Dataset>
    </Query>

Question: where I specify the build?
I think you have to select the correct host for your data: http://grch37.ensembl.org/biomart/martview