Dover Publications, also known as Dover Books, is an American book publisher founded in 1941 by Hayward and Blanche Cirker. It primarily reissues books that are out of print from their original publishers. These are often, but not always, books in the public domain. The original published editions may be scarce or historically significant. Dover republishes these books, making them available at a significantly reduced cost. Classic reprints Dover reprints classic works of literature, classical sheet music, and public-domain images from the 18th and 19th centuries. Dover also publishes an extensive collection of mathematical, scientific, and engineering texts. It often targets its reprints at a niche market, such as woodworking. Starting in 2015, the company branched out into graphic novel reprints, overseen by Dover acquisitions editor and former comics writer and editor Drew Ford. Most Dover reprints are photo facsimiles of the originals, retaining the original pagination and typeset, sometimes with a new introduction. Dover will usually add new and more colorful cover art to its paper-bound editions. They retitle some books to reflect modern dialect and categories. For example, the book Woodward's National Architect was retitled A Victorian Housebuilder's Guide. History The Cirkers started the business selling remaindered textbooks by mail. The company published its first book, Tables of Functions with Formulas and Curves, when the German copyright was voided by the United States as a result of World War II. The book was an unexpected success and established the Dover business model of publishing esoteric works at a low price. One of Dover's best sellers was Albert Einstein's The Principle of Relativity, which Einstein reluctantly agreed to republish despite his concerns that it was outdated. Dover helped to transform the paperback book market. In 1951 it issued some of the earliest standard-sized paperbacks, a format that became known as a trade paperback. Since the 1960s, the vast majority of Dover's titles have been paper-bound books of various sizes. Dover paperbacks had sewn pages, unlike most paperbacks which were held together with glue and subject to page drop-out. Beginning in the 1950s Dover also issued a series of Listen & Learn language courses prepared primarily using teachers from Columbia University. For a time, Dover also published a catalog of LP phonograph records. Some, such as selected recordings of Schubert's solo and chamber works featuring pianist Friedrich Wührer, were reissues of earlier monaural releases from other labels. Noteworthy among Dover's