General works on Latin American history have appeared since the 1950s, when the teaching of Latin American history expanded in U.S. universities and colleges. Most attempt full coverage of Spanish America and Brazil from the conquest to the modern era, focusing on institutional, political, social and economic history. An important, eleven volume treatment of Latin American history is "The Cambridge History of Latin America", with separate volumes on the colonial era, nineteenth century, and the twentieth century. There is a small number of general works that have gone through multiple editions. Major trade publishers have also issued edited volumes on Latin American history and historiography. Reference works include the Handbook of Latin American Studies, which publishes articles by area experts, with annotated bibliographic entries, and the "Encyclopedia of Latin American History and Culture".