PBA Galleries is holding its 447^th sale of rare books and manuscripts later today with three very different highlights.

There is a preliminary sketch by E H Shepard for A A Milne's The House at Pooh Corner. A rare example on the open market of one of Shepard's preliminary drawings for one of the Christopher Robin books - in 1969 he donated 300 of his preliminary sketches for the Pooh drawings to the Victoria and Albert Museum.

This example is said to have been presented to the director of a documentary about Shepard in the 1970s. It is slightly different from the published version. E H Shepard's illustrations are treasured by collectors and the $12,000-15,000 listing seems relatively modest.

Secondly there is the first printing of one of Shakespeare's tragedies, Coriolanus, from the first folio edition of 1623, and the earliest obtainable printing of this famous play. Shakespeare's First Folio is among the rarest, the most desirable and, to-date, perhaps the most expensive printed work in the English language.

The last substantially complete copy to exchange hands sold for $6.5m. For most collectors and scholars, complete individual plays such as this one offer the only opportunity to own one of the icons of English literature. This makes it a strong investment.

Finally, there is a remarkable full size facsimile reproduction of John James Audubon's landmark work on the birds of the North American continent.

The most American bird of all: Audubon's Eagle (Click to enlarge)

Originally published in London, issued in 87 parts between 1827 and 1838, Audubon's Birds is today among the rarest and most valuable books ever published. A complete set of the original edition sold for $11.6m at auction in December, 2010 achieving a new record for a printed book sold at auction.

The present facsimile faithfully reproduces the original in full colour from the copy held by the Teyler Foundation, Haarlem, The Netherlands. The set offered here has been housed in the four original shipping crates since publication, the last three of which were opened for the first time after arriving at our galleries.

Both the Shakespeare and the Audubon are expected to fetch $20,000-30,000 in the sale which takes place at 1pm local time in San Francisco, California today, February 14.