Par Gerald Nelson,Director Survey of English Usage Sidney Greenbaum,Sidney Greenbaum
https://books.google.dz/books?id=f6IuAgAAQBAJ&pg=PA16&lpg=PA16&dq=1)Sandra+is+my+mother%27s+name.PN&source=bl&ots=Sv98tBUiux&sig=lLDDm1ZZl5BKlcJQQIqzvW5t3GU&hl=fr&sa=X&redir_esc=y#v=onepage&q=1)Sandra%20is%20my%20mother%27s%20name.PN&f=false
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