CIA UFO Special Collection
https://www.cia.gov/library/readingroom/search/site/ufo
https://www.cia.gov/library/readingroom/advanced-search-view?keyword=unidentified+flying+objects&label=unidentified+flying+objects&sm_field_document_number=&sm_field_original_classification=&ds_field_pub_date_op=%3D&ds_field_pub_date%5Bvalue%5D=&ds_field_pub_date%5Bmin%5D=&ds_field_pub_date%5Bmax%5D=&sm_field_content_type=&sm_field_case_number=
https://www.cia.gov/library/readingroom/advanced-search-view?keyword=unidentified+flying+objects&label=ufo&sm_field_document_number=&sm_field_original_classification=&ds_field_pub_date_op=%3D&ds_field_pub_date%5Bvalue%5D=&ds_field_pub_date%5Bmin%5D=&ds_field_pub_date%5Bmax%5D=&sm_field_content_type=&sm_field_case_number=
https://www.cia.gov/library/readingroom/advanced-search-view?keyword= SIGHTINGS OF UNIDENTIFIED FLYING OBJECTS&label= SIGHTINGS OF UNIDENTIFIED FLYING OBJECTS&sm_field_document_number=&sm_field_original_classification=&ds_field_pub_date_op=%3D&ds_field_pub_date[value]=&ds_field_pub_date[min]=&ds_field_pub_date[max]=&sm_field_content_type=&sm_field_case_number=