“Yesterday is history. Tomorrow is a mystery. Today is a gift. ”

The quote is usually regarded as anonymous, but is often attributed to her on several websites, as well as in several books, including My Life Is an Open Book http://books.google.es/books?id=qCOa1k--dt4C&printsec=frontcover&hl=es#v=onepage&q=eleanor%20roosevelt&f=false (2008), The Spirituality of Mary Magdalene http://books.google.es/books?hl=es&id=BLRuINwzVZcC&dq=eleanor+roosevelt++%22past+is+history%22&q=eleanor+roosevelt#v=snippet&q=eleanor%20roosevelt&f=false (2008), Mis cuatro estaciones http://books.google.es/books?hl=es&id=QCgANqKq8EIC&dq=ayer+es+historia%2C+ma%C3%B1ana++misterio.+Hoy+regalo+de+Dios+presente&q=%22eleanor+roosevelt%22#v=snippet&q=%22eleanor%20roosevelt%22&f=false (2008), and Gilles Lamontagne http://books.google.es/books?ei=MdG9UqGQK-fL2wX5zYC4Dw&hl=es&id=WyFKAQAAIAAJ&dq=Hier+est+de+l%27histoire%2C+demain+est+un+myst%C3%A8re+et+aujourd%27hui+est+un+cadeau.+C%27+est+pourquoi+nous+l%27appelons+%C2%AB+le+pr%C3%A9sent+roosevelt&focus=searchwithinvolume&q=eleanor+roosevelt (2010). None of these works cite any original reference.
Disputed

On destiny - "The Shock Of Reality" http://allafrica.com/stories/200908240244.html All Africa (August 24 2009)

Estoy en el ayer, en el hoy. ¿Y en mañana? En el mañana estuve.
Voces (1943)

My Heart's in the Highlands (1939)

Source: The Lost Thing

Source: War and Peace

Source: The Sisterhood of the Traveling Pants

Source: Evermore