Correspondence (1990) with European Centre for Educational Alliances, International Council on Archives, ARSA, International Association of Universities, COEFA, CISS, AIAP, International Peace Research Association, North East NGOs, CIM, ICOM, NGO Standing Committee (meetings and reports on the 22nd NGO Conference, 11-15 June 1990), ICSU, UOIF
Correspondence and annual agreements between ICPHS and UNESCO: amount of subsidies granted to ICPHS and Diogenes, contracts and conditions, financial and moral reports on the use of funds (1985-1991)
Correspondence and annual agreements between ICPHS and UNESCO: amount of subsidies granted to ICPHS and Diogenes, contracts and conditions, financial reports on the use of funds (1950-1985)
Correspondence and working documents of the ICPHS concerning the sexennial reports of the UNESCO Executive Board on NGOs (1964-1969; 1970-1975; 1976-1982; 1983-1988; 1988-1993)
Correspondence of the General Secretariat with the members of the Bureau (1960): Charles E. Odegaard, Ronald Syme, Silvio Zavala, Felice Battaglia, Jules Marouzeau, Hans R. Hahnloser, R.N. Dandekar; general correspondence
Correspondence with the Federation of Documentation (Index bibliographicus) (1955-1956). Correspondence with international bibliographic companies, especially those published under the auspices of ICPHS (1957-1958)
Correspondence with UNESCO. Comments and suggestions to UNESCO's draft biannual programme and budget (1967 to 1983) Suggestions on UNESCO's medium-term plans (1973-1978; 1979-1983-1984-1989)