The 'papers' of Dirk Kruijt contain 135 magnetic tapes (also called cassettes) of interviews, a small amount of paper documents and some computer files. The paper documents (0.25 m.): drafts of transcriptions of a part of the 135 magnetic tapes; the transcriptions are 85 in number, all on Peru and most of these interviews were done in 1985-1986 for his book Revolution by Decree. Peru 1968-1975 (Amsterdam: Thela Publishers, 1994) and its translation in Spanish La Revolución por Decreto. El Perú durante el gobierno militar (Lima, 2008) but some interviews were held later on until 2002; Kruijts interviewees were key figures from the military socialist regime and the Peruvian society including Miguel de la Flor Valle , Carlos Gamarra , Graham Hurtado , Aníbal Meza Cuadra , Alberto Ruiz Eldredge and Arturo Valdés Palacio . The magnetic tapes are 135, with the following distribution by countries: 41 for Nicaragua, 36 for Guatemala, 29 for El Salvador, 25 for Peru and 3 for Costa Rica (plus 1); the list of the cassettes shows the wide range of people who were interviewed as the most important members of the 'guerrillero generation' as well as military or government officials in the countries of Central and Latin America. The oral interviews were realized by Dirk Kruijt around the government of Velasco Alvarado who lead the 'military socialist regime' in Peru (1968-1975) with the influence of the Liberation Theology and the Democrat Party; Kruijt spoke with the most influential men of Velasco’s regime as the General De la Flor Valle, Minister of Foreign Affairs ad member of the Presidential Advisory Committee, Jose Graham Hurtado, Director of the Presidential Advisory Committee (COAP), Arturo Valdes who was the Chief of the Cabinet Secretary and the best confident and friend of Velasco and Francisco Guerra García who had an important role in the institution in charge of the Agrarian Reform; some of these militaries were also important later on; this is the case of the General Robles who is in prison now because he has been accused for the crimes of insubordination; he said that he had been victimized because he denounced in 1993 a Death Squad known as the 'Colina Group' set up by Peru’s National Intelligence Service (SIN) and leaded, it is said, by Montesinos, the main advisor and Government Minister of President Fujimori (1990-2000).