More than 300 books including works by Nicolaus Copernicus, Albert Einstein and Charles Darwin are being offered at auction next week.

The single-owner collection, which also contains books by Karl Marx, Sir Isaac Newton and Johnannes Kepler, is expected to bring $6 million at Christie's New York auction on Tuesday.

A copy of Copernicus' "De revolutionibus orbium coelestium" (On the Revolutions of the Heavenly Spheres), printed in 1543, is expected to bring the highest price, between $900,000 and $1.2 million.

It puts forth Copernicus' theory that the sun — not the Earth — is at the center of the universe.

Christie's calls the Copernicus volume "arguable the finest copy in private hands."

The sale also includes the only known first edition of the first phone book, issued in 1878, two years after Alexander Graham Bell invented the telephone.

The 20-page, pamphlet-size book, published by the Connecticut District Telephone Company, contains the names and numbers of 391 New Haven area subscribers.

It also provides some helpful hints to callers: "Should you wish to speak to another subscriber you should commence the conversation by saying 'Hulloa!"'

It could fetch $30,000 to $40,000.

Einstein's own set of copies of his papers, including ones on the theories of special and general relativity, quantum theory and unified theory, is estimated to bring $150,000 to $250,000.

The collection is being sold by Richard Green, a retired physician and amateur astronomer from Long Island.