major exhibitions devoted to them. : A sub-collection consists of 13 volumes, 12 volumes released in 1992 and one in 1994, a larger format (210 × 270 mm) is used for them. : A 6-volume sub-collection released in 1998 (124 × 178 mm), inspired by the "Documents" section at the back of every Découvertes book. : A sub-collection of exhibition booklets created in 2018, with the smaller format (120 × 170 mm). The "Hors série" books are often coupled with art exhibitions and it works well. While the other attempts to diversify the collection have often resulted in resounding commercial failures, such as the "Albums" and "Texto". Despite an interesting concept: the use of still images from Gaumont archives for "Une autre histoire du XXe siècle", this series has had mixed success. English edition A small portion of the collection has been translated into English, published by Thames & Hudson in United Kingdom under the title New Horizons series, which launched its first titles in 1992 with the slogan, "the expanding universe between two covers". According to Thames & Hudson director Jamie Camplin, the remit is to "educate in an entertaining way". Paul Gottlieb, former director and editor in chief of the New York-based publisher Abrams Books (then called Harry N. Abrams), discovered Pierre Marchand's "Découvertes" at the Gallimard stand during the Bologna Book Fair in 1991, which he called "a dazzling array of books" and an "imaginative combination of text and pictures in a magnificently produced series of paperback books". He began to negotiate for English language translation. The collection was eventually titled Abrams Discoveries series by the U.S. publisher. They began to publish in the spring of 1992, and more than 100 titles were produced by 2008. The two publishers shared the translation costs, the American edition was then re-edited to take into account English spelling, or vice versa. Unlike the numbered French edition, American and British editions are not put into numerical order. UK edition's book spines have titles in white with black background, while the more Gallimard-style US edition has titles in colour and sometimes with decorative features, such as an for Cleopatra: The Life and Death of a Pharaoh and a for Heraldry: An Introduction to a Noble Tradition. Apart from spelling and punctuation differences, certain titles of American edition have additional explanation placed in parentheses within the body text. For instance, in The Celts: