A rare typescript of Antoine de Saint-Exupery's "The Little Prince," containing extensive handwritten corrections by the French author and described by book dealers as "literary treasure," will soon go on sale for $1.25 million.

A candidate for the world's most translated book outside of religious texts, the novella about a child who travels from planet to planet gaining wisdom was published in 1943 at the height of World War II.

Bound in a worn, black cover, the French-language typescript of "Le Petit Prince" was written in New York during the author's exile from Nazi-occupied France, just before he left to serve in the Free French Air Force fighting the occupation.

The other two of the three known copies in existence sit in France's national library and the Harry Ransom Center in Texas.

The typescript features what is thought to be the first written appearance of one of the book's most famous lines: "It is only with the heart that one can see rightly; the essential is invisible to the eye."

Rare book dealers crave editions that get to the heart of an author's creative process, especially in influential works such as "The Little Prince," said Sammy Jay, Senior Literature Specialist at Peter Harrington Rare Books, which is selling the book.

"This is quite simply the most exceptional example of that that I've ever seen or had the opportunity to be involved with."

"It's a high point, and I feel almost a little poignant about it, because I don't quite see how I'm ever going to beat this," said Jay, a book dealer and collector for 13 years.

Besides the handwritten corrections, the typescript contains two original pencil sketches by the author including an early sketch for the book's final illustration of the little prince returning home.

Saint-Exupery died in 1944 when his plane disappeared during a military reconnaissance mission over the Mediterranean.

The book, which recently came out of private hands, will be on sale at Abu Dhabi Art from Nov. 20-24.