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Records relating to The Organization for Economic Cooperation and Development would be part of Record Group 59, "General Records of the Department of State." You can find information on these records on the National Archives Catalog here: https://www.archives.gov/research/catalog . You can narrow your search using the specific areas of interest you have listed. For instance, I entered the search terms " OECD and Japan" and received the following results: https://catalog.archives.gov/search?q=japan%20OECD
Links for general OECD records:
A great resource is also Is The State Department's, Office of the Historian ( https://history.state.gov/historicaldocuments.) You can search for relevant key words and it will give the filing decimal for any relevant documents. While this may not provide access to digitized documents, it will aid in your requests if you were ever to make the trip to the National Archives.
Some of the records you can access on these sites have been digitized and are accessible online. However, for more information regarding Record Group 59, or to speak with an archivist, Contact The National Archives at College Park's Textual Reference Branch via email at Archives2reference@nara.gov
Due to the COVID-19 pandemic and pursuant to guidance received from the Office of Management and Budget (OMB), NARA has adjusted its normal operations to balance the need of completing its mission-critical work while also adhering to the recommended social distancing for the safety of NARA staff. As a result of this re-prioritization of activities, you may experience a delay in receiving an initial acknowledgement as well as a substantive response to your reference request from RDT2. We apologize for this inconvenience and appreciate your understanding and patience.
We hope this information is helpful. Best of luck with your research!
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