convertToXMLReferences = input => {
  let output = ''
  ;[...input].forEach(ch => {
    const c = ch.charCodeAt()
    output += c <= 127 ? ch : `&#${c};`
  })
  return output
}
Converts a string to use XML references (for non-ASCII).
@function module:utilities.convertToXMLReferences
@param {string} input
@returns {string} Decimal numeric character references