According to Elza Soares Wikipedia entry, her first husband was named Lourdes Antônio Soares.
Can 'Lourdes' be a boy's name in Brazil? Is this information correct?
Since Elsa took her husbands name 'Soares', I assume 'Soares' is here correctly given as her husband's last name.
To me "Antônio Lourdes" would sound more masculine, in the same way as 'José Maria' is a masculine name.