Collection consisting of internal IS correspondence (for the most part copies) in French, English and Italian, concerning disputes and ideological debates in and between the different national sections; concerning the splits in which the various national sections were involved, including extensive correspondence between Jon Horelick and Tony Verlaan; correspondence with editors and publishers; files on the IS conference in Venice 1969 and the delegates conference in Wolsfeld 1970; file on the strategic debate of April/May 1970; translations of IS texts and articles and texts inspired by the IS or referring to the IS, published in various countries; documents concerning the AFGES and other leaflets and printed material 1962-1971; press clippings on the IS 1964-1971.