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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _parse_references(xml):
 """Parse the references to ``Reference`` instances."""

    references = []
    ref_finder = HTMLReferenceFinder(xml)
    for elm, uri_attr in ref_finder:
        type_ = _discover_uri_type(elm.get(uri_attr))
        references.append(Reference(elm, type_, uri_attr))
    return references